---
_id: '10855'
abstract:
- lang: eng
  text: 'Consider a distributed task where the communication network is fixed but
    the local inputs given to the nodes of the distributed system may change over
    time. In this work, we explore the following question: if some of the local inputs
    change, can an existing solution be updated efficiently, in a dynamic and distributed
    manner? To address this question, we define the batch dynamic \congest model in
    which we are given a bandwidth-limited communication network and a dynamic edge
    labelling defines the problem input. The task is to maintain a solution to a graph
    problem on the labeled graph under batch changes. We investigate, when a batch
    of α edge label changes arrive, \beginitemize \item how much time as a function
    of α we need to update an existing solution, and \item how much information the
    nodes have to keep in local memory between batches in order to update the solution
    quickly. \enditemize Our work lays the foundations for the theory of input-dynamic
    distributed network algorithms. We give a general picture of the complexity landscape
    in this model, design both universal algorithms and algorithms for concrete problems,
    and present a general framework for lower bounds. In particular, we derive non-trivial
    upper bounds for two selected, contrasting problems: maintaining a minimum spanning
    tree and detecting cliques.'
acknowledgement: "We thank Jukka Suomela for discussions. We also thank our shepherd
  Mohammad Hajiesmaili\r\nand the reviewers for their time and suggestions on how
  to improve the paper. This project\r\nhas received funding from the European Research
  Council (ERC) under the European Union’s\r\nHorizon 2020 research and innovation
  programme (grant agreement No 805223 ScaleML), from the European Union’s Horizon
  2020 research and innovation programme under the Marie\r\nSk lodowska–Curie grant
  agreement No. 840605, from the Vienna Science and Technology Fund (WWTF) project
  WHATIF, ICT19-045, 2020-2024, and from the Austrian Science Fund (FWF) and netIDEE
  SCIENCE project P 33775-N."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Klaus-Tycho
  full_name: Foerster, Klaus-Tycho
  last_name: Foerster
- first_name: Janne
  full_name: Korhonen, Janne
  id: C5402D42-15BC-11E9-A202-CA2BE6697425
  last_name: Korhonen
- first_name: Ami
  full_name: Paz, Ami
  last_name: Paz
- first_name: Joel
  full_name: Rybicki, Joel
  id: 334EFD2E-F248-11E8-B48F-1D18A9856A87
  last_name: Rybicki
  orcid: 0000-0002-6432-6646
- first_name: Stefan
  full_name: Schmid, Stefan
  last_name: Schmid
citation:
  ama: Foerster K-T, Korhonen J, Paz A, Rybicki J, Schmid S. Input-dynamic distributed
    algorithms for communication networks. <i>Proceedings of the ACM on Measurement
    and Analysis of Computing Systems</i>. 2021;5(1):1-33. doi:<a href="https://doi.org/10.1145/3447384">10.1145/3447384</a>
  apa: Foerster, K.-T., Korhonen, J., Paz, A., Rybicki, J., &#38; Schmid, S. (2021).
    Input-dynamic distributed algorithms for communication networks. <i>Proceedings
    of the ACM on Measurement and Analysis of Computing Systems</i>. Association for
    Computing Machinery. <a href="https://doi.org/10.1145/3447384">https://doi.org/10.1145/3447384</a>
  chicago: Foerster, Klaus-Tycho, Janne Korhonen, Ami Paz, Joel Rybicki, and Stefan
    Schmid. “Input-Dynamic Distributed Algorithms for Communication Networks.” <i>Proceedings
    of the ACM on Measurement and Analysis of Computing Systems</i>. Association for
    Computing Machinery, 2021. <a href="https://doi.org/10.1145/3447384">https://doi.org/10.1145/3447384</a>.
  ieee: K.-T. Foerster, J. Korhonen, A. Paz, J. Rybicki, and S. Schmid, “Input-dynamic
    distributed algorithms for communication networks,” <i>Proceedings of the ACM
    on Measurement and Analysis of Computing Systems</i>, vol. 5, no. 1. Association
    for Computing Machinery, pp. 1–33, 2021.
  ista: Foerster K-T, Korhonen J, Paz A, Rybicki J, Schmid S. 2021. Input-dynamic
    distributed algorithms for communication networks. Proceedings of the ACM on Measurement
    and Analysis of Computing Systems. 5(1), 1–33.
  mla: Foerster, Klaus-Tycho, et al. “Input-Dynamic Distributed Algorithms for Communication
    Networks.” <i>Proceedings of the ACM on Measurement and Analysis of Computing
    Systems</i>, vol. 5, no. 1, Association for Computing Machinery, 2021, pp. 1–33,
    doi:<a href="https://doi.org/10.1145/3447384">10.1145/3447384</a>.
  short: K.-T. Foerster, J. Korhonen, A. Paz, J. Rybicki, S. Schmid, Proceedings of
    the ACM on Measurement and Analysis of Computing Systems 5 (2021) 1–33.
date_created: 2022-03-18T09:10:27Z
date_published: 2021-03-01T00:00:00Z
date_updated: 2025-04-14T13:52:09Z
day: '01'
department:
- _id: DaAl
doi: 10.1145/3447384
ec_funded: 1
external_id:
  arxiv:
  - '2005.07637'
intvolume: '         5'
issue: '1'
keyword:
- Computer Networks and Communications
- Hardware and Architecture
- Safety
- Risk
- Reliability and Quality
- Computer Science (miscellaneous)
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2005.07637
month: '03'
oa: 1
oa_version: Preprint
page: 1-33
project:
- _id: 26A5D39A-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '840605'
  name: Coordination in constrained and natural distributed systems
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: Proceedings of the ACM on Measurement and Analysis of Computing Systems
publication_identifier:
  issn:
  - 2476-1249
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
related_material:
  record:
  - id: '10854'
    relation: shorter_version
    status: public
scopus_import: '1'
status: public
title: Input-dynamic distributed algorithms for communication networks
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 5
year: '2021'
...
---
_id: '11458'
abstract:
- lang: eng
  text: 'The increasing computational requirements of deep neural networks (DNNs)
    have led to significant interest in obtaining DNN models that are sparse, yet
    accurate. Recent work has investigated the even harder case of sparse training,
    where the DNN weights are, for as much as possible, already sparse to reduce computational
    costs during training. Existing sparse training methods are often empirical and
    can have lower accuracy relative to the dense baseline. In this paper, we present
    a general approach called Alternating Compressed/DeCompressed (AC/DC) training
    of DNNs, demonstrate convergence for a variant of the algorithm, and show that
    AC/DC outperforms existing sparse training methods in accuracy at similar computational
    budgets; at high sparsity levels, AC/DC even outperforms existing methods that
    rely on accurate pre-trained dense models. An important property of AC/DC is that
    it allows co-training of dense and sparse models, yielding accurate sparse–dense
    model pairs at the end of the training process. This is useful in practice, where
    compressed variants may be desirable for deployment in resource-constrained settings
    without re-doing the entire training flow, and also provides us with insights
    into the accuracy gap between dense and compressed models. The code is available
    at: https://github.com/IST-DASLab/ACDC.'
acknowledged_ssus:
- _id: ScienComp
acknowledgement: This project has received funding from the European Research Council
  (ERC) under the European Union’s Horizon 2020 research and innovation programme
  (grant agreement No 805223 ScaleML), and a CNRS PEPS grant. This research was supported
  by the Scientific Service Units (SSU) of IST Austria through resources provided
  by Scientific Computing (SciComp). We would also like to thank Christoph Lampert
  for his feedback on an earlier version of this work, as well as for providing hardware
  for the Transformer-XL experiments.
alternative_title:
- Advances in Neural Information Processing Systems
article_processing_charge: No
arxiv: 1
author:
- first_name: Elena-Alexandra
  full_name: Peste, Elena-Alexandra
  id: 32D78294-F248-11E8-B48F-1D18A9856A87
  last_name: Peste
- first_name: Eugenia B
  full_name: Iofinova, Eugenia B
  id: f9a17499-f6e0-11ea-865d-fdf9a3f77117
  last_name: Iofinova
  orcid: 0000-0002-7778-3221
- first_name: Adrian
  full_name: Vladu, Adrian
  last_name: Vladu
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
citation:
  ama: 'Krumes A, Iofinova EB, Vladu A, Alistarh D-A. AC/DC: Alternating Compressed/DeCompressed
    training of deep neural networks. In: <i>35th Conference on Neural Information
    Processing Systems</i>. Vol 34. Neural Information Processing Systems Foundation;
    2021:8557-8570.'
  apa: 'Krumes, A., Iofinova, E. B., Vladu, A., &#38; Alistarh, D.-A. (2021). AC/DC:
    Alternating Compressed/DeCompressed training of deep neural networks. In <i>35th
    Conference on Neural Information Processing Systems</i> (Vol. 34, pp. 8557–8570).
    Virtual, Online: Neural Information Processing Systems Foundation.'
  chicago: 'Krumes, Alexandra, Eugenia B Iofinova, Adrian Vladu, and Dan-Adrian Alistarh.
    “AC/DC: Alternating Compressed/DeCompressed Training of Deep Neural Networks.”
    In <i>35th Conference on Neural Information Processing Systems</i>, 34:8557–70.
    Neural Information Processing Systems Foundation, 2021.'
  ieee: 'A. Krumes, E. B. Iofinova, A. Vladu, and D.-A. Alistarh, “AC/DC: Alternating
    Compressed/DeCompressed training of deep neural networks,” in <i>35th Conference
    on Neural Information Processing Systems</i>, Virtual, Online, 2021, vol. 34,
    pp. 8557–8570.'
  ista: 'Krumes A, Iofinova EB, Vladu A, Alistarh D-A. 2021. AC/DC: Alternating Compressed/DeCompressed
    training of deep neural networks. 35th Conference on Neural Information Processing
    Systems. NeurIPS: Neural Information Processing Systems, Advances in Neural Information
    Processing Systems, vol. 34, 8557–8570.'
  mla: 'Krumes, Alexandra, et al. “AC/DC: Alternating Compressed/DeCompressed Training
    of Deep Neural Networks.” <i>35th Conference on Neural Information Processing
    Systems</i>, vol. 34, Neural Information Processing Systems Foundation, 2021,
    pp. 8557–70.'
  short: A. Krumes, E.B. Iofinova, A. Vladu, D.-A. Alistarh, in:, 35th Conference
    on Neural Information Processing Systems, Neural Information Processing Systems
    Foundation, 2021, pp. 8557–8570.
conference:
  end_date: 2021-12-14
  location: Virtual, Online
  name: 'NeurIPS: Neural Information Processing Systems'
  start_date: 2021-12-06
corr_author: '1'
date_created: 2022-06-20T12:11:53Z
date_published: 2021-12-06T00:00:00Z
date_updated: 2026-06-18T17:18:20Z
day: '06'
ddc:
- '000'
department:
- _id: GradSch
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '2106.12379'
intvolume: '        34'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://proceedings.neurips.cc/paper/2021/file/48000647b315f6f00f913caa757a70b3-Paper.pdf
month: '12'
oa: 1
oa_version: Published Version
page: 8557-8570
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th Conference on Neural Information Processing Systems
publication_identifier:
  isbn:
  - '9781713845393'
  issn:
  - 1049-5258
publication_status: published
publisher: Neural Information Processing Systems Foundation
quality_controlled: '1'
related_material:
  record:
  - id: '13074'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: 'AC/DC: Alternating Compressed/DeCompressed training of deep neural networks'
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2021'
...
---
_id: '11463'
abstract:
- lang: eng
  text: "Efficiently approximating local curvature information of the loss function
    is a key tool for optimization and compression of deep neural networks. Yet, most
    existing methods to approximate second-order information have high computational\r\nor
    storage costs, which limits their practicality. In this work, we investigate matrix-free,
    linear-time approaches for estimating Inverse-Hessian Vector Products (IHVPs)
    for the case when the Hessian can be approximated as a sum of rank-one matrices,
    as in the classic approximation of the Hessian by the empirical Fisher matrix.
    We propose two new algorithms: the first is tailored towards network compression
    and can compute the IHVP for dimension d, if the Hessian is given as a sum of
    m rank-one matrices, using O(dm2) precomputation, O(dm) cost for computing the
    IHVP, and query cost O(m) for any single element of the inverse Hessian. The second
    algorithm targets an optimization setting, where we wish to compute the product
    between the inverse Hessian, estimated over a sliding window of optimization steps,
    and a given gradient direction, as required for preconditioned SGD. We give an
    algorithm with cost O(dm + m2) for computing the IHVP and O(dm + m3) for adding
    or removing any gradient from the sliding window. These\r\ntwo algorithms yield
    state-of-the-art results for network pruning and optimization with lower computational
    overhead relative to existing second-order methods. Implementations are available
    at [9] and [17]."
acknowledgement: We gratefully acknowledge funding the European Research Council (ERC)
  under the European Union’s Horizon 2020 research and innovation programme (grant
  agreement No 805223 ScaleML), as well as computational support from Amazon Web Services
  (AWS) EC2.
alternative_title:
- Advances in Neural Information Processing Systems
article_processing_charge: No
arxiv: 1
author:
- first_name: Elias
  full_name: Frantar, Elias
  id: 09a8f98d-ec99-11ea-ae11-c063a7b7fe5f
  last_name: Frantar
- first_name: Eldar
  full_name: Kurtic, Eldar
  id: 47beb3a5-07b5-11eb-9b87-b108ec578218
  last_name: Kurtic
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
citation:
  ama: 'Frantar E, Kurtic E, Alistarh D-A. M-FAC: Efficient matrix-free approximations
    of second-order information. In: <i>35th Conference on Neural Information Processing
    Systems</i>. Vol 34. Neural Information Processing Systems Foundation; 2021:14873-14886.'
  apa: 'Frantar, E., Kurtic, E., &#38; Alistarh, D.-A. (2021). M-FAC: Efficient matrix-free
    approximations of second-order information. In <i>35th Conference on Neural Information
    Processing Systems</i> (Vol. 34, pp. 14873–14886). Virtual, Online: Neural Information
    Processing Systems Foundation.'
  chicago: 'Frantar, Elias, Eldar Kurtic, and Dan-Adrian Alistarh. “M-FAC: Efficient
    Matrix-Free Approximations of Second-Order Information.” In <i>35th Conference
    on Neural Information Processing Systems</i>, 34:14873–86. Neural Information
    Processing Systems Foundation, 2021.'
  ieee: 'E. Frantar, E. Kurtic, and D.-A. Alistarh, “M-FAC: Efficient matrix-free
    approximations of second-order information,” in <i>35th Conference on Neural Information
    Processing Systems</i>, Virtual, Online, 2021, vol. 34, pp. 14873–14886.'
  ista: 'Frantar E, Kurtic E, Alistarh D-A. 2021. M-FAC: Efficient matrix-free approximations
    of second-order information. 35th Conference on Neural Information Processing
    Systems. NeurIPS: Neural Information Processing Systems, Advances in Neural Information
    Processing Systems, vol. 34, 14873–14886.'
  mla: 'Frantar, Elias, et al. “M-FAC: Efficient Matrix-Free Approximations of Second-Order
    Information.” <i>35th Conference on Neural Information Processing Systems</i>,
    vol. 34, Neural Information Processing Systems Foundation, 2021, pp. 14873–86.'
  short: E. Frantar, E. Kurtic, D.-A. Alistarh, in:, 35th Conference on Neural Information
    Processing Systems, Neural Information Processing Systems Foundation, 2021, pp.
    14873–14886.
conference:
  end_date: 2021-12-14
  location: Virtual, Online
  name: 'NeurIPS: Neural Information Processing Systems'
  start_date: 2021-12-06
corr_author: '1'
date_created: 2022-06-26T22:01:35Z
date_published: 2021-12-06T00:00:00Z
date_updated: 2026-06-18T17:18:44Z
day: '06'
ddc:
- '000'
department:
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '2010.08222'
intvolume: '        34'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://proceedings.neurips.cc/paper/2021/file/7cfd5df443b4eb0d69886a583b33de4c-Paper.pdf
month: '12'
oa: 1
oa_version: Published Version
page: 14873-14886
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th Conference on Neural Information Processing Systems
publication_identifier:
  isbn:
  - '9781713845393'
  issn:
  - 1049-5258
publication_status: published
publisher: Neural Information Processing Systems Foundation
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'M-FAC: Efficient matrix-free approximations of second-order information'
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2021'
...
---
_id: '11464'
abstract:
- lang: eng
  text: "We consider a standard distributed optimisation setting where N machines,
    each holding a d-dimensional function\r\nfi, aim to jointly minimise the sum of
    the functions ∑Ni=1fi(x). This problem arises naturally in large-scale distributed
    optimisation, where a standard solution is to apply variants of (stochastic) gradient
    descent. We focus on the communication complexity of this problem: our main result
    provides the first fully unconditional bounds on total number of bits which need
    to be sent and received by the N machines to solve this problem under point-to-point
    communication, within a given error-tolerance. Specifically, we show that Ω(Ndlogd/Nε)
    total bits need to be communicated between the machines to find an additive ϵ-approximation
    to the minimum of ∑Ni=1fi(x). The result holds for both deterministic and randomised
    algorithms, and, importantly, requires no assumptions on the algorithm structure.
    The lower bound is tight under certain restrictions on parameter values, and is
    matched within constant factors for quadratic objectives by a new variant of quantised
    gradient descent, which we describe and analyse. Our results bring over tools
    from communication complexity to distributed optimisation, which has potential
    for further applications."
acknowledgement: We thank the NeurIPS reviewers for insightful comments that helped
  us improve the positioning of our results, as well as for pointing out the subsampling
  approach for complementing the randomised lower bound. We also thank Foivos Alimisis
  and Peter Davies for useful discussions. This project has received funding from
  the European Research Council (ERC) under the European Union’s Horizon 2020 research
  and innovation programme (grant agreement No 805223 ScaleML).
alternative_title:
- Advances in Neural Information Processing Systems
article_processing_charge: No
arxiv: 1
author:
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Janne
  full_name: Korhonen, Janne
  id: C5402D42-15BC-11E9-A202-CA2BE6697425
  last_name: Korhonen
citation:
  ama: 'Alistarh D-A, Korhonen J. Towards tight communication lower bounds for distributed
    optimisation. In: <i>35th Conference on Neural Information Processing Systems</i>.
    Vol 34. Neural Information Processing Systems Foundation; 2021:7254-7266.'
  apa: 'Alistarh, D.-A., &#38; Korhonen, J. (2021). Towards tight communication lower
    bounds for distributed optimisation. In <i>35th Conference on Neural Information
    Processing Systems</i> (Vol. 34, pp. 7254–7266). Virtual, Online: Neural Information
    Processing Systems Foundation.'
  chicago: Alistarh, Dan-Adrian, and Janne Korhonen. “Towards Tight Communication
    Lower Bounds for Distributed Optimisation.” In <i>35th Conference on Neural Information
    Processing Systems</i>, 34:7254–66. Neural Information Processing Systems Foundation,
    2021.
  ieee: D.-A. Alistarh and J. Korhonen, “Towards tight communication lower bounds
    for distributed optimisation,” in <i>35th Conference on Neural Information Processing
    Systems</i>, Virtual, Online, 2021, vol. 34, pp. 7254–7266.
  ista: 'Alistarh D-A, Korhonen J. 2021. Towards tight communication lower bounds
    for distributed optimisation. 35th Conference on Neural Information Processing
    Systems. NeurIPS: Neural Information Processing Systems, Advances in Neural Information
    Processing Systems, vol. 34, 7254–7266.'
  mla: Alistarh, Dan-Adrian, and Janne Korhonen. “Towards Tight Communication Lower
    Bounds for Distributed Optimisation.” <i>35th Conference on Neural Information
    Processing Systems</i>, vol. 34, Neural Information Processing Systems Foundation,
    2021, pp. 7254–66.
  short: D.-A. Alistarh, J. Korhonen, in:, 35th Conference on Neural Information Processing
    Systems, Neural Information Processing Systems Foundation, 2021, pp. 7254–7266.
conference:
  end_date: 2021-12-14
  location: Virtual, Online
  name: 'NeurIPS: Neural Information Processing Systems'
  start_date: 2021-12-06
corr_author: '1'
date_created: 2022-06-26T22:01:35Z
date_published: 2021-12-06T00:00:00Z
date_updated: 2026-06-18T17:19:18Z
day: '06'
ddc:
- '000'
department:
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '2010.08222'
intvolume: '        34'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://proceedings.neurips.cc/paper/2021/file/3b92d18aa7a6176dd37d372bc2f1eb71-Paper.pdf
month: '12'
oa: 1
oa_version: Published Version
page: 7254-7266
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th Conference on Neural Information Processing Systems
publication_identifier:
  isbn:
  - '9781713845393'
  issn:
  - 1049-5258
publication_status: published
publisher: Neural Information Processing Systems Foundation
quality_controlled: '1'
scopus_import: '1'
status: public
title: Towards tight communication lower bounds for distributed optimisation
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2021'
...
---
_id: '13147'
abstract:
- lang: eng
  text: "We investigate fast and communication-efficient algorithms for the classic
    problem of minimizing a sum of strongly convex and smooth functions that are distributed
    among n\r\n different nodes, which can communicate using a limited number of bits.
    Most previous communication-efficient approaches for this problem are limited
    to first-order optimization, and therefore have \\emph{linear} dependence on the
    condition number in their communication complexity. We show that this dependence
    is not inherent: communication-efficient methods can in fact have sublinear dependence
    on the condition number. For this, we design and analyze the first communication-efficient
    distributed variants of preconditioned gradient descent for Generalized Linear
    Models, and for Newton’s method. Our results rely on a new technique for quantizing
    both the preconditioner and the descent direction at each step of the algorithms,
    while controlling their convergence rate. We also validate our findings experimentally,
    showing faster convergence and reduced communication relative to previous methods."
acknowledgement: The authors would like to thank Janne Korhonen, Aurelien Lucchi,
  Celestine MendlerDunner and Antonio Orvieto for helpful discussions. FA ¨and DA
  were supported during this work by the European Research Council (ERC) under the
  European Union’s Horizon 2020 research and innovation programme (grant agreement
  No 805223 ScaleML). PD was supported by the European Union’s Horizon 2020 programme
  under the Marie Skłodowska-Curie grant agreement No. 754411.
article_processing_charge: No
arxiv: 1
author:
- first_name: Foivos
  full_name: Alimisis, Foivos
  last_name: Alimisis
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
citation:
  ama: 'Alimisis F, Davies P, Alistarh D-A. Communication-efficient distributed optimization
    with quantized preconditioners. In: <i>Proceedings of the 38th International Conference
    on Machine Learning</i>. Vol 139. ML Research Press; 2021:196-206.'
  apa: 'Alimisis, F., Davies, P., &#38; Alistarh, D.-A. (2021). Communication-efficient
    distributed optimization with quantized preconditioners. In <i>Proceedings of
    the 38th International Conference on Machine Learning</i> (Vol. 139, pp. 196–206).
    Virtual: ML Research Press.'
  chicago: Alimisis, Foivos, Peter Davies, and Dan-Adrian Alistarh. “Communication-Efficient
    Distributed Optimization with Quantized Preconditioners.” In <i>Proceedings of
    the 38th International Conference on Machine Learning</i>, 139:196–206. ML Research
    Press, 2021.
  ieee: F. Alimisis, P. Davies, and D.-A. Alistarh, “Communication-efficient distributed
    optimization with quantized preconditioners,” in <i>Proceedings of the 38th International
    Conference on Machine Learning</i>, Virtual, 2021, vol. 139, pp. 196–206.
  ista: 'Alimisis F, Davies P, Alistarh D-A. 2021. Communication-efficient distributed
    optimization with quantized preconditioners. Proceedings of the 38th International
    Conference on Machine Learning. ICML: International Conference on Machine Learning
    vol. 139, 196–206.'
  mla: Alimisis, Foivos, et al. “Communication-Efficient Distributed Optimization
    with Quantized Preconditioners.” <i>Proceedings of the 38th International Conference
    on Machine Learning</i>, vol. 139, ML Research Press, 2021, pp. 196–206.
  short: F. Alimisis, P. Davies, D.-A. Alistarh, in:, Proceedings of the 38th International
    Conference on Machine Learning, ML Research Press, 2021, pp. 196–206.
conference:
  end_date: 2021-07-24
  location: Virtual
  name: 'ICML: International Conference on Machine Learning'
  start_date: 2021-07-18
corr_author: '1'
date_created: 2023-06-18T22:00:48Z
date_published: 2021-07-01T00:00:00Z
date_updated: 2025-07-10T11:50:37Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '2102.07214'
file:
- access_level: open_access
  checksum: 7ec0d59bac268b49c76bf2e036dedd7a
  content_type: application/pdf
  creator: dernst
  date_created: 2023-06-19T10:41:05Z
  date_updated: 2023-06-19T10:41:05Z
  file_id: '13154'
  file_name: 2021_PMLR_Alimisis.pdf
  file_size: 429087
  relation: main_file
  success: 1
file_date_updated: 2023-06-19T10:41:05Z
has_accepted_license: '1'
intvolume: '       139'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: 196-206
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Proceedings of the 38th International Conference on Machine Learning
publication_identifier:
  eissn:
  - 2640-3498
  isbn:
  - '9781713845065'
publication_status: published
publisher: ML Research Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Communication-efficient distributed optimization with quantized preconditioners
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 139
year: '2021'
...
---
_id: '15263'
abstract:
- lang: eng
  text: We develop a new Riemannian descent algorithm that relies on momentum to improve
    over existing first-order methods for geodesically convex optimization. In contrast,
    accelerated convergence rates proved in prior work have only been shown to hold
    for geodesically strongly-convex objective functions. We further extend our algorithm
    to geodesically weakly-quasi-convex objectives. Our proofs of convergence rely
    on a novel estimate sequence that illustrates the dependency of the convergence
    rate on the curvature of the manifold. We validate our theoretical results empirically
    on several optimization problems defined on the sphere and on the manifold of
    positive definite matrices.
acknowledgement: The authors would like to thank professors Nicolas Boumal and Suvrit
  Sra for helpful discussions on the content of this paper. Gary Bécigneul was funded
  by the Max Planck ETH Center for Learning Systems during the course of this work.
alternative_title:
- PMLR
article_processing_charge: No
arxiv: 1
author:
- first_name: Foivos
  full_name: Alimisis, Foivos
  id: 19430a34-05f6-11ef-890d-c079cfc60ae2
  last_name: Alimisis
- first_name: Antonio
  full_name: Orvieto, Antonio
  last_name: Orvieto
- first_name: Gary
  full_name: Becigneul, Gary
  last_name: Becigneul
- first_name: Aurelien
  full_name: Lucchi, Aurelien
  last_name: Lucchi
citation:
  ama: 'Alimisis F, Orvieto A, Becigneul G, Lucchi A. Momentum improves optimization
    on Riemannian manifolds. In: <i>Proceedings of the 24th International Conference
    on Artificial Intelligence and Statistics</i>. Vol 130. ML Research Press; 2021:1351-1359.'
  apa: 'Alimisis, F., Orvieto, A., Becigneul, G., &#38; Lucchi, A. (2021). Momentum
    improves optimization on Riemannian manifolds. In <i>Proceedings of the 24th International
    Conference on Artificial Intelligence and Statistics</i> (Vol. 130, pp. 1351–1359).
    San Diego, CA, United States; Virtual: ML Research Press.'
  chicago: Alimisis, Foivos, Antonio Orvieto, Gary Becigneul, and Aurelien Lucchi.
    “Momentum Improves Optimization on Riemannian Manifolds.” In <i>Proceedings of
    the 24th International Conference on Artificial Intelligence and Statistics</i>,
    130:1351–59. ML Research Press, 2021.
  ieee: F. Alimisis, A. Orvieto, G. Becigneul, and A. Lucchi, “Momentum improves optimization
    on Riemannian manifolds,” in <i>Proceedings of the 24th International Conference
    on Artificial Intelligence and Statistics</i>, San Diego, CA, United States; Virtual,
    2021, vol. 130, pp. 1351–1359.
  ista: 'Alimisis F, Orvieto A, Becigneul G, Lucchi A. 2021. Momentum improves optimization
    on Riemannian manifolds. Proceedings of the 24th International Conference on Artificial
    Intelligence and Statistics. AISTATS: Conference on Artificial Intelligence and
    Statistics, PMLR, vol. 130, 1351–1359.'
  mla: Alimisis, Foivos, et al. “Momentum Improves Optimization on Riemannian Manifolds.”
    <i>Proceedings of the 24th International Conference on Artificial Intelligence
    and Statistics</i>, vol. 130, ML Research Press, 2021, pp. 1351–59.
  short: F. Alimisis, A. Orvieto, G. Becigneul, A. Lucchi, in:, Proceedings of the
    24th International Conference on Artificial Intelligence and Statistics, ML Research
    Press, 2021, pp. 1351–1359.
conference:
  end_date: 2021-04-15
  location: San Diego, CA, United States; Virtual
  name: 'AISTATS: Conference on Artificial Intelligence and Statistics'
  start_date: 2021-04-13
date_created: 2024-04-03T07:29:49Z
date_published: 2021-04-15T00:00:00Z
date_updated: 2026-06-18T17:47:19Z
day: '15'
ddc:
- '000'
department:
- _id: DaAl
external_id:
  arxiv:
  - '2002.04144'
intvolume: '       130'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://proceedings.mlr.press/v130/alimisis21a.html
month: '04'
oa: 1
oa_version: Published Version
page: 1351-1359
publication: Proceedings of the 24th International Conference on Artificial Intelligence
  and Statistics
publication_status: published
publisher: ML Research Press
quality_controlled: '1'
status: public
title: Momentum improves optimization on Riemannian manifolds
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 130
year: '2021'
...
---
_id: '15271'
abstract:
- lang: eng
  text: 'We settle the complexity of the (∆ + 1)-coloring and (∆ + 1)-list coloring
    problems intheCONGESTED CLIQUEmodel by presenting a simpledeterministicalgorithm
    for both problemsrunning in a constant number of rounds.  This matches the complexity
    of the recent breakthroughrandomizedconstant-round (∆ + 1)-list coloring algorithm
    due to Chang et al.  [Proceedings of the38th  ACM  Symposium  on  Principles  of  Distributed  Computing,  2019]  and  significantly  improvesupon
    the state-of-the-artO(log ∆)-round deterministic (∆ + 1)-coloring bound of Parter
    [Proceed-ings of the 45th Annual International Colloquium on Automata, Languages
    and Programming].  Aremarkable property of our algorithm is its simplicity.  Whereas
    the state-of-the-artrandomizedal-gorithms for this problem are based on the quite
    involved local coloring algorithm of Chang, Li, andPettie [Proceedings of the
    50th Annual ACM SIGACT Symposium on Theory of Computing, 2018],our algorithm can
    be described in just a few lines.  At a high level, it applies a careful derandomiza-tion
    of a recursive procedure which partitions the nodes and their respective palettes
    into separatebins.  We show that afterO(1) recursion steps, the remaining uncolored
    subgraph within each bin haslinear size and thus can be solved locally by collecting
    it to a single node.  This algorithm can alsobe implemented in the massively parallel
    computation (MPC) model provided that each machine haslinear (inn, the number
    of nodes in the input graph) space.  We also show an extension of our algo-rithm
    to theMPCregime, in which machines havesublinearspace:  we present the first deterministic(∆
    + 1)-list coloring algorithm designed for sublinear-spaceMPC, which runs inO(log
    ∆ + log logn)rounds.'
acknowledgement: The  first  author  was  partially  supported  by  the  Centre  for  Discrete  Mathematics
  and its Applications, by the IBM Faculty Award, and by the EPSRC award EP/N011163/1.  The
  second author was partially supported by the European Union’s Horizon 2020 research
  and innovation program under the Marie Sklodowska-Curie grant agreement 754411.  The
  first and third authors were partially supported by a Weizmann-UK Making Connections
  grant.
article_processing_charge: No
article_type: original
author:
- first_name: Artur
  full_name: Czumaj, Artur
  last_name: Czumaj
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
- first_name: Merav
  full_name: Parter, Merav
  last_name: Parter
citation:
  ama: Czumaj A, Davies P, Parter M. Simple, deterministic, constant-round coloring
    in congested clique and MPC. <i>SIAM Journal on Computing</i>. 2021;50(5):1603-1626.
    doi:<a href="https://doi.org/10.1137/20m1366502">10.1137/20m1366502</a>
  apa: Czumaj, A., Davies, P., &#38; Parter, M. (2021). Simple, deterministic, constant-round
    coloring in congested clique and MPC. <i>SIAM Journal on Computing</i>. Society
    for Industrial and Applied Mathematics. <a href="https://doi.org/10.1137/20m1366502">https://doi.org/10.1137/20m1366502</a>
  chicago: Czumaj, Artur, Peter Davies, and Merav Parter. “Simple, Deterministic,
    Constant-Round Coloring in Congested Clique and MPC.” <i>SIAM Journal on Computing</i>.
    Society for Industrial and Applied Mathematics, 2021. <a href="https://doi.org/10.1137/20m1366502">https://doi.org/10.1137/20m1366502</a>.
  ieee: A. Czumaj, P. Davies, and M. Parter, “Simple, deterministic, constant-round
    coloring in congested clique and MPC,” <i>SIAM Journal on Computing</i>, vol.
    50, no. 5. Society for Industrial and Applied Mathematics, pp. 1603–1626, 2021.
  ista: Czumaj A, Davies P, Parter M. 2021. Simple, deterministic, constant-round
    coloring in congested clique and MPC. SIAM Journal on Computing. 50(5), 1603–1626.
  mla: Czumaj, Artur, et al. “Simple, Deterministic, Constant-Round Coloring in Congested
    Clique and MPC.” <i>SIAM Journal on Computing</i>, vol. 50, no. 5, Society for
    Industrial and Applied Mathematics, 2021, pp. 1603–26, doi:<a href="https://doi.org/10.1137/20m1366502">10.1137/20m1366502</a>.
  short: A. Czumaj, P. Davies, M. Parter, SIAM Journal on Computing 50 (2021) 1603–1626.
date_created: 2024-04-03T07:53:22Z
date_published: 2021-01-01T00:00:00Z
date_updated: 2025-09-10T10:14:11Z
day: '01'
department:
- _id: DaAl
doi: 10.1137/20m1366502
ec_funded: 1
external_id:
  isi:
  - '000713008600004'
intvolume: '        50'
isi: 1
issue: '5'
keyword:
- General Mathematics
- General Computer Science
language:
- iso: eng
month: '01'
oa_version: None
page: 1603-1626
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: SIAM Journal on Computing
publication_identifier:
  eissn:
  - 1095-7111
  issn:
  - 0097-5397
publication_status: published
publisher: Society for Industrial and Applied Mathematics
quality_controlled: '1'
scopus_import: '1'
status: public
title: Simple, deterministic, constant-round coloring in congested clique and MPC
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 50
year: '2021'
...
---
_id: '10049'
abstract:
- lang: eng
  text: While messaging systems with strong security guarantees are widely used in
    practice, designing a protocol that scales efficiently to large groups and enjoys
    similar security guarantees remains largely open. The two existing proposals to
    date are ART (Cohn-Gordon et al., CCS18) and TreeKEM (IETF, The Messaging Layer
    Security Protocol, draft). TreeKEM is the currently considered candidate by the
    IETF MLS working group, but dynamic group operations (i.e. adding and removing
    users) can cause efficiency issues. In this paper we formalize and analyze a variant
    of TreeKEM which we term Tainted TreeKEM (TTKEM for short). The basic idea underlying
    TTKEM was suggested by Millican (MLS mailing list, February 2018). This version
    is more efficient than TreeKEM for some natural distributions of group operations,
    we quantify this through simulations.Our second contribution is two security proofs
    for TTKEM which establish post compromise and forward secrecy even against adaptive
    attackers. The security loss (to the underlying PKE) in the Random Oracle Model
    is a polynomial factor, and a quasipolynomial one in the Standard Model. Our proofs
    can be adapted to TreeKEM as well. Before our work no security proof for any TreeKEM-like
    protocol establishing tight security against an adversary who can adaptively choose
    the sequence of operations was known. We also are the first to prove (or even
    formalize) active security where the server can arbitrarily deviate from the protocol
    specification. Proving fully active security – where also the users can arbitrarily
    deviate – remains open.
acknowledgement: The first three authors contributed equally to this work. Funded
  by the European Research Council (ERC) under the European Union’s Horizon2020 research
  and innovation programme (682815-TOCNeT). Funded by the European Union’s Horizon
  2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement
  No.665385.
article_processing_charge: No
author:
- first_name: Karen
  full_name: Klein, Karen
  id: 3E83A2F8-F248-11E8-B48F-1D18A9856A87
  last_name: Klein
- first_name: Guillermo
  full_name: Pascual Perez, Guillermo
  id: 2D7ABD02-F248-11E8-B48F-1D18A9856A87
  last_name: Pascual Perez
  orcid: 0000-0001-8630-415X
- first_name: Michael
  full_name: Walter, Michael
  id: 488F98B0-F248-11E8-B48F-1D18A9856A87
  last_name: Walter
  orcid: 0000-0003-3186-2482
- first_name: Chethan
  full_name: Kamath Hosdurg, Chethan
  id: 4BD3F30E-F248-11E8-B48F-1D18A9856A87
  last_name: Kamath Hosdurg
  orcid: 0009-0006-6812-7317
- first_name: Margarita
  full_name: Capretto, Margarita
  last_name: Capretto
- first_name: Miguel
  full_name: Cueto Noval, Miguel
  id: ffc563a3-f6e0-11ea-865d-e3cce03d17cc
  last_name: Cueto Noval
  orcid: 0000-0002-2505-4246
- first_name: Ilia
  full_name: Markov, Ilia
  id: D0CF4148-C985-11E9-8066-0BDEE5697425
  last_name: Markov
- first_name: Michelle X
  full_name: Yeo, Michelle X
  id: 2D82B818-F248-11E8-B48F-1D18A9856A87
  last_name: Yeo
  orcid: 0009-0001-3676-4809
- first_name: Joel F
  full_name: Alwen, Joel F
  id: 2A8DFA8C-F248-11E8-B48F-1D18A9856A87
  last_name: Alwen
- first_name: Krzysztof Z
  full_name: Pietrzak, Krzysztof Z
  id: 3E04A7AA-F248-11E8-B48F-1D18A9856A87
  last_name: Pietrzak
  orcid: 0000-0002-9139-1654
citation:
  ama: 'Klein K, Pascual Perez G, Walter M, et al. Keep the dirt: tainted TreeKEM,
    adaptively and actively secure continuous group key agreement. In: <i>2021 IEEE
    Symposium on Security and Privacy </i>. IEEE; 2021:268-284. doi:<a href="https://doi.org/10.1109/sp40001.2021.00035">10.1109/sp40001.2021.00035</a>'
  apa: 'Klein, K., Pascual Perez, G., Walter, M., Kamath Hosdurg, C., Capretto, M.,
    Cueto Noval, M., … Pietrzak, K. Z. (2021). Keep the dirt: tainted TreeKEM, adaptively
    and actively secure continuous group key agreement. In <i>2021 IEEE Symposium
    on Security and Privacy </i> (pp. 268–284). San Francisco, CA, United States:
    IEEE. <a href="https://doi.org/10.1109/sp40001.2021.00035">https://doi.org/10.1109/sp40001.2021.00035</a>'
  chicago: 'Klein, Karen, Guillermo Pascual Perez, Michael Walter, Chethan Kamath
    Hosdurg, Margarita Capretto, Miguel Cueto Noval, Ilia Markov, Michelle X Yeo,
    Joel F Alwen, and Krzysztof Z Pietrzak. “Keep the Dirt: Tainted TreeKEM, Adaptively
    and Actively Secure Continuous Group Key Agreement.” In <i>2021 IEEE Symposium
    on Security and Privacy </i>, 268–84. IEEE, 2021. <a href="https://doi.org/10.1109/sp40001.2021.00035">https://doi.org/10.1109/sp40001.2021.00035</a>.'
  ieee: 'K. Klein <i>et al.</i>, “Keep the dirt: tainted TreeKEM, adaptively and actively
    secure continuous group key agreement,” in <i>2021 IEEE Symposium on Security
    and Privacy </i>, San Francisco, CA, United States, 2021, pp. 268–284.'
  ista: 'Klein K, Pascual Perez G, Walter M, Kamath Hosdurg C, Capretto M, Cueto Noval
    M, Markov I, Yeo MX, Alwen JF, Pietrzak KZ. 2021. Keep the dirt: tainted TreeKEM,
    adaptively and actively secure continuous group key agreement. 2021 IEEE Symposium
    on Security and Privacy . SP: Symposium on Security and Privacy, 268–284.'
  mla: 'Klein, Karen, et al. “Keep the Dirt: Tainted TreeKEM, Adaptively and Actively
    Secure Continuous Group Key Agreement.” <i>2021 IEEE Symposium on Security and
    Privacy </i>, IEEE, 2021, pp. 268–84, doi:<a href="https://doi.org/10.1109/sp40001.2021.00035">10.1109/sp40001.2021.00035</a>.'
  short: K. Klein, G. Pascual Perez, M. Walter, C. Kamath Hosdurg, M. Capretto, M.
    Cueto Noval, I. Markov, M.X. Yeo, J.F. Alwen, K.Z. Pietrzak, in:, 2021 IEEE Symposium
    on Security and Privacy , IEEE, 2021, pp. 268–284.
conference:
  end_date: 2021-05-27
  location: San Francisco, CA, United States
  name: 'SP: Symposium on Security and Privacy'
  start_date: 2021-05-24
corr_author: '1'
date_created: 2021-09-27T13:46:27Z
date_published: 2021-08-26T00:00:00Z
date_updated: 2026-04-08T07:01:44Z
day: '26'
department:
- _id: KrPi
- _id: DaAl
doi: 10.1109/sp40001.2021.00035
ec_funded: 1
external_id:
  isi:
  - '001316065000016'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://eprint.iacr.org/2019/1489
month: '08'
oa: 1
oa_version: Preprint
page: 268-284
project:
- _id: 2564DBCA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '665385'
  name: International IST Doctoral Program
- _id: 258AA5B2-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '682815'
  name: Teaching Old Crypto New Tricks
publication: '2021 IEEE Symposium on Security and Privacy '
publication_status: published
publisher: IEEE
quality_controlled: '1'
related_material:
  record:
  - id: '18088'
    relation: dissertation_contains
    status: public
  - id: '10035'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: 'Keep the dirt: tainted TreeKEM, adaptively and actively secure continuous
  group key agreement'
type: conference
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
year: '2021'
...
---
OA_place: publisher
_id: '10180'
abstract:
- lang: eng
  text: The growing energy and performance costs of deep learning have driven the
    community to reduce the size of neural networks by selectively pruning components.
    Similarly to their biological counterparts, sparse networks generalize just as
    well, sometimes even better than, the original dense networks. Sparsity promises
    to reduce the memory footprint of regular networks to fit mobile devices, as well
    as shorten training time for ever growing networks. In this paper, we survey prior
    work on sparsity in deep learning and provide an extensive tutorial of sparsification
    for both inference and training. We describe approaches to remove and add elements
    of neural networks, different training strategies to achieve model sparsity, and
    mechanisms to exploit sparsity in practice. Our work distills ideas from more
    than 300 research papers and provides guidance to practitioners who wish to utilize
    sparsity today, as well as to researchers whose goal is to push the frontier forward.
    We include the necessary background on mathematical methods in sparsification,
    describe phenomena such as early structure adaptation, the intricate relations
    between sparsity and the training process, and show techniques for achieving acceleration
    on real hardware. We also define a metric of pruned parameter efficiency that
    could serve as a baseline for comparison of different sparse networks. We close
    by speculating on how sparsity can improve future workloads and outline major
    open problems in the field.
acknowledgement: "We thank Doug Burger, Steve Scott, Marco Heddes, and the respective
  teams at Microsoft for inspiring discussions on the topic. We thank Angelika Steger
  for uplifting debates about the connections to biological brains, Sidak Pal Singh
  for his support regarding experimental results, and Utku Evci as well as Xin Wang
  for comments on previous versions of this\r\nwork. Special thanks go to Bernhard
  Schölkopf, our JMLR editor Samy Bengio, and the three anonymous reviewers who provided
  excellent comprehensive, pointed, and deep review comments that improved the quality
  of our manuscript significantly."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Torsten
  full_name: Hoefler, Torsten
  last_name: Hoefler
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Tal
  full_name: Ben-Nun, Tal
  last_name: Ben-Nun
- first_name: Nikoli
  full_name: Dryden, Nikoli
  last_name: Dryden
- first_name: Elena-Alexandra
  full_name: Peste, Elena-Alexandra
  id: 32D78294-F248-11E8-B48F-1D18A9856A87
  last_name: Peste
citation:
  ama: 'Hoefler T, Alistarh D-A, Ben-Nun T, Dryden N, Krumes A. Sparsity in deep learning:
    Pruning and growth for efficient inference and training in neural networks. <i>Journal
    of Machine Learning Research</i>. 2021;22(241):1-124.'
  apa: 'Hoefler, T., Alistarh, D.-A., Ben-Nun, T., Dryden, N., &#38; Krumes, A. (2021).
    Sparsity in deep learning: Pruning and growth for efficient inference and training
    in neural networks. <i>Journal of Machine Learning Research</i>. ML Research Press.'
  chicago: 'Hoefler, Torsten, Dan-Adrian Alistarh, Tal Ben-Nun, Nikoli Dryden, and
    Alexandra Krumes. “Sparsity in Deep Learning: Pruning and Growth for Efficient
    Inference and Training in Neural Networks.” <i>Journal of Machine Learning Research</i>.
    ML Research Press, 2021.'
  ieee: 'T. Hoefler, D.-A. Alistarh, T. Ben-Nun, N. Dryden, and A. Krumes, “Sparsity
    in deep learning: Pruning and growth for efficient inference and training in neural
    networks,” <i>Journal of Machine Learning Research</i>, vol. 22, no. 241. ML Research
    Press, pp. 1–124, 2021.'
  ista: 'Hoefler T, Alistarh D-A, Ben-Nun T, Dryden N, Krumes A. 2021. Sparsity in
    deep learning: Pruning and growth for efficient inference and training in neural
    networks. Journal of Machine Learning Research. 22(241), 1–124.'
  mla: 'Hoefler, Torsten, et al. “Sparsity in Deep Learning: Pruning and Growth for
    Efficient Inference and Training in Neural Networks.” <i>Journal of Machine Learning
    Research</i>, vol. 22, no. 241, ML Research Press, 2021, pp. 1–124.'
  short: T. Hoefler, D.-A. Alistarh, T. Ben-Nun, N. Dryden, A. Krumes, Journal of
    Machine Learning Research 22 (2021) 1–124.
corr_author: '1'
date_created: 2021-10-24T22:01:34Z
date_published: 2021-09-01T00:00:00Z
date_updated: 2025-06-26T11:53:12Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
external_id:
  arxiv:
  - '2102.00554'
file:
- access_level: open_access
  checksum: 3389d9d01fc58f8fb4c1a53e14a8abbf
  content_type: application/pdf
  creator: cziletti
  date_created: 2021-10-27T15:34:18Z
  date_updated: 2021-10-27T15:34:18Z
  file_id: '10192'
  file_name: 2021_JMachLearnRes_Hoefler.pdf
  file_size: 3527521
  relation: main_file
  success: 1
file_date_updated: 2021-10-27T15:34:18Z
has_accepted_license: '1'
intvolume: '        22'
issue: '241'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.jmlr.org/papers/v22/21-0366.html
month: '09'
oa: 1
oa_version: Published Version
page: 1-124
publication: Journal of Machine Learning Research
publication_identifier:
  eissn:
  - 1533-7928
  issn:
  - 1532-4435
publication_status: published
publisher: ML Research Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Sparsity in deep learning: Pruning and growth for efficient inference and
  training in neural networks'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 22
year: '2021'
...
---
_id: '10216'
abstract:
- lang: eng
  text: 'This paper reports a new concurrent graph data structure that supports updates
    of both edges and vertices and queries: Breadth-first search, Single-source shortest-path,
    and Betweenness centrality. The operations are provably linearizable and non-blocking.'
acknowledgement: "This work was partially funded by National Supercomputing Mission,
  Govt. of India under the project “Concurrent and Distributed Programming primitives
  and algorithms for Temporal Graphs”(DST/NSM/R&D_Exascale/2021/16).\r\n"
alternative_title:
- LIPIcs
article_number: '52'
article_processing_charge: No
arxiv: 1
author:
- first_name: Bapi
  full_name: Chatterjee, Bapi
  id: 3C41A08A-F248-11E8-B48F-1D18A9856A87
  last_name: Chatterjee
  orcid: 0000-0002-2742-4028
- first_name: Sathya
  full_name: Peri, Sathya
  last_name: Peri
- first_name: Muktikanta
  full_name: Sa, Muktikanta
  last_name: Sa
citation:
  ama: 'Chatterjee B, Peri S, Sa M. Brief announcement: Non-blocking dynamic unbounded
    graphs with worst-case amortized bounds. In: <i>35th International Symposium on
    Distributed Computing</i>. Vol 209. Schloss Dagstuhl - Leibniz-Zentrum für Informatik;
    2021. doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.52">10.4230/LIPIcs.DISC.2021.52</a>'
  apa: 'Chatterjee, B., Peri, S., &#38; Sa, M. (2021). Brief announcement: Non-blocking
    dynamic unbounded graphs with worst-case amortized bounds. In <i>35th International
    Symposium on Distributed Computing</i> (Vol. 209). Freiburg, Germany: Schloss
    Dagstuhl - Leibniz-Zentrum für Informatik. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.52">https://doi.org/10.4230/LIPIcs.DISC.2021.52</a>'
  chicago: 'Chatterjee, Bapi, Sathya Peri, and Muktikanta Sa. “Brief Announcement:
    Non-Blocking Dynamic Unbounded Graphs with Worst-Case Amortized Bounds.” In <i>35th
    International Symposium on Distributed Computing</i>, Vol. 209. Schloss Dagstuhl
    - Leibniz-Zentrum für Informatik, 2021. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.52">https://doi.org/10.4230/LIPIcs.DISC.2021.52</a>.'
  ieee: 'B. Chatterjee, S. Peri, and M. Sa, “Brief announcement: Non-blocking dynamic
    unbounded graphs with worst-case amortized bounds,” in <i>35th International Symposium
    on Distributed Computing</i>, Freiburg, Germany, 2021, vol. 209.'
  ista: 'Chatterjee B, Peri S, Sa M. 2021. Brief announcement: Non-blocking dynamic
    unbounded graphs with worst-case amortized bounds. 35th International Symposium
    on Distributed Computing. DISC: Distributed Computing, LIPIcs, vol. 209, 52.'
  mla: 'Chatterjee, Bapi, et al. “Brief Announcement: Non-Blocking Dynamic Unbounded
    Graphs with Worst-Case Amortized Bounds.” <i>35th International Symposium on Distributed
    Computing</i>, vol. 209, 52, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2021, doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.52">10.4230/LIPIcs.DISC.2021.52</a>.'
  short: B. Chatterjee, S. Peri, M. Sa, in:, 35th International Symposium on Distributed
    Computing, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021.
conference:
  end_date: 2021-10-08
  location: Freiburg, Germany
  name: 'DISC: Distributed Computing'
  start_date: 2021-10-04
date_created: 2021-11-07T23:01:23Z
date_published: 2021-10-04T00:00:00Z
date_updated: 2025-05-14T10:54:39Z
day: '04'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.4230/LIPIcs.DISC.2021.52
external_id:
  arxiv:
  - '2003.01697'
file:
- access_level: open_access
  checksum: 76546df112a0ba1166c864d33d7834e2
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-12T09:23:22Z
  date_updated: 2021-11-12T09:23:22Z
  file_id: '10276'
  file_name: 2021_LIPIcsDISC_BChatterjee.pdf
  file_size: 795860
  relation: main_file
  success: 1
file_date_updated: 2021-11-12T09:23:22Z
has_accepted_license: '1'
intvolume: '       209'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
publication: 35th International Symposium on Distributed Computing
publication_identifier:
  isbn:
  - 9-783-9597-7210-5
  issn:
  - 1868-8969
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Brief announcement: Non-blocking dynamic unbounded graphs with worst-case
  amortized bounds'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 209
year: '2021'
...
---
_id: '10217'
abstract:
- lang: eng
  text: This paper gives tight logarithmic lower bounds on the solo step complexity
    of leader election in an asynchronous shared-memory model with single-writer multi-reader
    (SWMR) registers, for both deterministic and randomized obstruction-free algorithms.
    The approach extends to lower bounds for deterministic and randomized obstruction-free
    algorithms using multi-writer registers under bounded write concurrency, showing
    a trade-off between the solo step complexity of a leader election algorithm, and
    the worst-case number of stalls incurred by a processor in an execution.
acknowledgement: "Dan Alistarh: Supported in part by the European Research Council
  (ERC) under the European Union’s Horizon 2020 research and innovation programme
  (grant agreement No 805223 ScaleML). Giorgi Nadiradze: Supported in part by the
  European Research Council (ERC) under the European Union’s Horizon 2020 research
  and innovation programme (grant agreement No 805223 ScaleML). The authors would
  like to thank the DISC anonymous reviewers for their useful\r\nfeedback and comments."
alternative_title:
- LIPIcs
article_number: '4'
article_processing_charge: No
author:
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Rati
  full_name: Gelashvili, Rati
  last_name: Gelashvili
- first_name: Giorgi
  full_name: Nadiradze, Giorgi
  id: 3279A00C-F248-11E8-B48F-1D18A9856A87
  last_name: Nadiradze
  orcid: 0000-0001-5634-0731
citation:
  ama: 'Alistarh D-A, Gelashvili R, Nadiradze G. Lower bounds for shared-memory leader
    election under bounded write contention. In: <i>35th International Symposium on
    Distributed Computing</i>. Vol 209. Schloss Dagstuhl - Leibniz-Zentrum für Informatik;
    2021. doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.4">10.4230/LIPIcs.DISC.2021.4</a>'
  apa: 'Alistarh, D.-A., Gelashvili, R., &#38; Nadiradze, G. (2021). Lower bounds
    for shared-memory leader election under bounded write contention. In <i>35th International
    Symposium on Distributed Computing</i> (Vol. 209). Freiburg, Germany: Schloss
    Dagstuhl - Leibniz-Zentrum für Informatik. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.4">https://doi.org/10.4230/LIPIcs.DISC.2021.4</a>'
  chicago: Alistarh, Dan-Adrian, Rati Gelashvili, and Giorgi Nadiradze. “Lower Bounds
    for Shared-Memory Leader Election under Bounded Write Contention.” In <i>35th
    International Symposium on Distributed Computing</i>, Vol. 209. Schloss Dagstuhl
    - Leibniz-Zentrum für Informatik, 2021. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.4">https://doi.org/10.4230/LIPIcs.DISC.2021.4</a>.
  ieee: D.-A. Alistarh, R. Gelashvili, and G. Nadiradze, “Lower bounds for shared-memory
    leader election under bounded write contention,” in <i>35th International Symposium
    on Distributed Computing</i>, Freiburg, Germany, 2021, vol. 209.
  ista: 'Alistarh D-A, Gelashvili R, Nadiradze G. 2021. Lower bounds for shared-memory
    leader election under bounded write contention. 35th International Symposium on
    Distributed Computing. DISC: Distributed Computing, LIPIcs, vol. 209, 4.'
  mla: Alistarh, Dan-Adrian, et al. “Lower Bounds for Shared-Memory Leader Election
    under Bounded Write Contention.” <i>35th International Symposium on Distributed
    Computing</i>, vol. 209, 4, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2021, doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.4">10.4230/LIPIcs.DISC.2021.4</a>.
  short: D.-A. Alistarh, R. Gelashvili, G. Nadiradze, in:, 35th International Symposium
    on Distributed Computing, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021.
conference:
  end_date: 2021-10-08
  location: Freiburg, Germany
  name: 'DISC: Distributed Computing'
  start_date: 2021-10-04
date_created: 2021-11-07T23:01:23Z
date_published: 2021-10-04T00:00:00Z
date_updated: 2025-05-14T10:54:30Z
day: '04'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.4230/LIPIcs.DISC.2021.4
ec_funded: 1
file:
- access_level: open_access
  checksum: b4cdc6668c899a601c5e6a96b8ca54d9
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-12T09:33:26Z
  date_updated: 2021-11-12T09:33:26Z
  file_id: '10277'
  file_name: 2021_LIPIcsDISC_Alistarh.pdf
  file_size: 706791
  relation: main_file
  success: 1
file_date_updated: 2021-11-12T09:33:26Z
has_accepted_license: '1'
intvolume: '       209'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th International Symposium on Distributed Computing
publication_identifier:
  isbn:
  - 9-783-9597-7210-5
  issn:
  - 1868-8969
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: Lower bounds for shared-memory leader election under bounded write contention
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 209
year: '2021'
...
---
_id: '10218'
abstract:
- lang: eng
  text: 'Let G be a graph on n nodes. In the stochastic population protocol model,
    a collection of n indistinguishable, resource-limited nodes collectively solve
    tasks via pairwise interactions. In each interaction, two randomly chosen neighbors
    first read each other’s states, and then update their local states. A rich line
    of research has established tight upper and lower bounds on the complexity of
    fundamental tasks, such as majority and leader election, in this model, when G
    is a clique. Specifically, in the clique, these tasks can be solved fast, i.e.,
    in n polylog n pairwise interactions, with high probability, using at most polylog
    n states per node. In this work, we consider the more general setting where G
    is an arbitrary graph, and present a technique for simulating protocols designed
    for fully-connected networks in any connected regular graph. Our main result is
    a simulation that is efficient on many interesting graph families: roughly, the
    simulation overhead is polylogarithmic in the number of nodes, and quadratic in
    the conductance of the graph. As an example, this implies that, in any regular
    graph with conductance φ, both leader election and exact majority can be solved
    in φ^{-2} ⋅ n polylog n pairwise interactions, with high probability, using at
    most φ^{-2} ⋅ polylog n states per node. This shows that there are fast and space-efficient
    population protocols for leader election and exact majority on graphs with good
    expansion properties.'
acknowledgement: This project has received funding from the European Union’s Horizon
  2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement
  No 840605.
alternative_title:
- LIPIcs
article_number: '43'
article_processing_charge: No
arxiv: 1
author:
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Rati
  full_name: Gelashvili, Rati
  last_name: Gelashvili
- first_name: Joel
  full_name: Rybicki, Joel
  id: 334EFD2E-F248-11E8-B48F-1D18A9856A87
  last_name: Rybicki
  orcid: 0000-0002-6432-6646
citation:
  ama: 'Alistarh D-A, Gelashvili R, Rybicki J. Brief announcement: Fast graphical
    population protocols. In: <i>35th International Symposium on Distributed Computing</i>.
    Vol 209. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2021. doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.43">10.4230/LIPIcs.DISC.2021.43</a>'
  apa: 'Alistarh, D.-A., Gelashvili, R., &#38; Rybicki, J. (2021). Brief announcement:
    Fast graphical population protocols. In <i>35th International Symposium on Distributed
    Computing</i> (Vol. 209). Freiburg, Germany: Schloss Dagstuhl - Leibniz-Zentrum
    für Informatik. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.43">https://doi.org/10.4230/LIPIcs.DISC.2021.43</a>'
  chicago: 'Alistarh, Dan-Adrian, Rati Gelashvili, and Joel Rybicki. “Brief Announcement:
    Fast Graphical Population Protocols.” In <i>35th International Symposium on Distributed
    Computing</i>, Vol. 209. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021.
    <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.43">https://doi.org/10.4230/LIPIcs.DISC.2021.43</a>.'
  ieee: 'D.-A. Alistarh, R. Gelashvili, and J. Rybicki, “Brief announcement: Fast
    graphical population protocols,” in <i>35th International Symposium on Distributed
    Computing</i>, Freiburg, Germany, 2021, vol. 209.'
  ista: 'Alistarh D-A, Gelashvili R, Rybicki J. 2021. Brief announcement: Fast graphical
    population protocols. 35th International Symposium on Distributed Computing. DISC:
    Distributed Computing , LIPIcs, vol. 209, 43.'
  mla: 'Alistarh, Dan-Adrian, et al. “Brief Announcement: Fast Graphical Population
    Protocols.” <i>35th International Symposium on Distributed Computing</i>, vol.
    209, 43, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021, doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.43">10.4230/LIPIcs.DISC.2021.43</a>.'
  short: D.-A. Alistarh, R. Gelashvili, J. Rybicki, in:, 35th International Symposium
    on Distributed Computing, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021.
conference:
  end_date: 2021-10-08
  location: Freiburg, Germany
  name: 'DISC: Distributed Computing '
  start_date: 2021-10-04
date_created: 2021-11-07T23:01:24Z
date_published: 2021-10-04T00:00:00Z
date_updated: 2025-04-14T07:50:55Z
day: '04'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.4230/LIPIcs.DISC.2021.43
ec_funded: 1
external_id:
  arxiv:
  - '2102.08808'
file:
- access_level: open_access
  checksum: fd2a690f6856d21247e9aa952b0e2885
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-12T08:16:44Z
  date_updated: 2021-11-12T08:16:44Z
  file_id: '10274'
  file_name: 2021_LIPIcsDISC_Alistarh.pdf
  file_size: 534219
  relation: main_file
  success: 1
file_date_updated: 2021-11-12T08:16:44Z
has_accepted_license: '1'
intvolume: '       209'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
project:
- _id: 26A5D39A-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '840605'
  name: Coordination in constrained and natural distributed systems
publication: 35th International Symposium on Distributed Computing
publication_identifier:
  isbn:
  - 9-783-9597-7210-5
  issn:
  - 1868-8969
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Brief announcement: Fast graphical population protocols'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
volume: 209
year: '2021'
...
---
_id: '10219'
abstract:
- lang: eng
  text: We show that any algorithm that solves the sinkless orientation problem in
    the supported LOCAL model requires Ω(log n) rounds, and this is tight. The supported
    LOCAL is at least as strong as the usual LOCAL model, and as a corollary this
    also gives a new, short and elementary proof that shows that the round complexity
    of the sinkless orientation problem in the deterministic LOCAL model is Ω(log
    n).
acknowledgement: "Janne H. Korhonen: Project has received funding from the European
  Research Council (ERC) under the European Union’s Horizon 2020 research and innovation
  programme (grant agreement No 805223 ScaleML). Ami Paz: We acknowledge the Austrian
  Science Fund (FWF) and netIDEE SCIENCE project P 33775-N. Stefan Schmid: Research
  supported by the Austrian Science Fund (FWF) project ADVISE, I 4800-N, 2020-2023.\r\n"
alternative_title:
- LIPIcs
article_number: '58'
article_processing_charge: No
arxiv: 1
author:
- first_name: Janne
  full_name: Korhonen, Janne
  id: C5402D42-15BC-11E9-A202-CA2BE6697425
  last_name: Korhonen
- first_name: Ami
  full_name: Paz, Ami
  last_name: Paz
- first_name: Joel
  full_name: Rybicki, Joel
  id: 334EFD2E-F248-11E8-B48F-1D18A9856A87
  last_name: Rybicki
  orcid: 0000-0002-6432-6646
- first_name: Stefan
  full_name: Schmid, Stefan
  last_name: Schmid
- first_name: Jukka
  full_name: Suomela, Jukka
  last_name: Suomela
citation:
  ama: 'Korhonen J, Paz A, Rybicki J, Schmid S, Suomela J. Brief announcement: Sinkless
    orientation is hard also in the supported LOCAL model. In: <i>35th International
    Symposium on Distributed Computing</i>. Vol 209. Schloss Dagstuhl - Leibniz-Zentrum
    für Informatik; 2021. doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.58">10.4230/LIPIcs.DISC.2021.58</a>'
  apa: 'Korhonen, J., Paz, A., Rybicki, J., Schmid, S., &#38; Suomela, J. (2021).
    Brief announcement: Sinkless orientation is hard also in the supported LOCAL model.
    In <i>35th International Symposium on Distributed Computing</i> (Vol. 209). Freiburg,
    Germany: Schloss Dagstuhl - Leibniz-Zentrum für Informatik. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.58">https://doi.org/10.4230/LIPIcs.DISC.2021.58</a>'
  chicago: 'Korhonen, Janne, Ami Paz, Joel Rybicki, Stefan Schmid, and Jukka Suomela.
    “Brief Announcement: Sinkless Orientation Is Hard Also in the Supported LOCAL
    Model.” In <i>35th International Symposium on Distributed Computing</i>, Vol.
    209. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2021. <a href="https://doi.org/10.4230/LIPIcs.DISC.2021.58">https://doi.org/10.4230/LIPIcs.DISC.2021.58</a>.'
  ieee: 'J. Korhonen, A. Paz, J. Rybicki, S. Schmid, and J. Suomela, “Brief announcement:
    Sinkless orientation is hard also in the supported LOCAL model,” in <i>35th International
    Symposium on Distributed Computing</i>, Freiburg, Germany, 2021, vol. 209.'
  ista: 'Korhonen J, Paz A, Rybicki J, Schmid S, Suomela J. 2021. Brief announcement:
    Sinkless orientation is hard also in the supported LOCAL model. 35th International
    Symposium on Distributed Computing. DISC: Distributed Computing , LIPIcs, vol.
    209, 58.'
  mla: 'Korhonen, Janne, et al. “Brief Announcement: Sinkless Orientation Is Hard
    Also in the Supported LOCAL Model.” <i>35th International Symposium on Distributed
    Computing</i>, vol. 209, 58, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2021, doi:<a href="https://doi.org/10.4230/LIPIcs.DISC.2021.58">10.4230/LIPIcs.DISC.2021.58</a>.'
  short: J. Korhonen, A. Paz, J. Rybicki, S. Schmid, J. Suomela, in:, 35th International
    Symposium on Distributed Computing, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2021.
conference:
  end_date: 2021-10-08
  location: Freiburg, Germany
  name: 'DISC: Distributed Computing '
  start_date: 2021-10-04
date_created: 2021-11-07T23:01:24Z
date_published: 2021-10-04T00:00:00Z
date_updated: 2025-05-14T10:54:13Z
day: '04'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.4230/LIPIcs.DISC.2021.58
ec_funded: 1
external_id:
  arxiv:
  - '2108.02655'
file:
- access_level: open_access
  checksum: c43188dc2070bbd2bf5fd6fdaf9ce36d
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-12T08:27:42Z
  date_updated: 2021-11-12T08:27:42Z
  file_id: '10275'
  file_name: 2021_LIPIcsDISC_Korhonen.pdf
  file_size: 474242
  relation: main_file
  success: 1
file_date_updated: 2021-11-12T08:27:42Z
has_accepted_license: '1'
intvolume: '       209'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th International Symposium on Distributed Computing
publication_identifier:
  isbn:
  - 9-783-9597-7210-5
  issn:
  - 1868-8969
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Brief announcement: Sinkless orientation is hard also in the supported LOCAL
  model'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 209
year: '2021'
...
---
_id: '10435'
abstract:
- lang: eng
  text: Decentralized optimization is emerging as a viable alternative for scalable
    distributed machine learning, but also introduces new challenges in terms of synchronization
    costs. To this end, several communication-reduction techniques, such as non-blocking
    communication, quantization, and local steps, have been explored in the decentralized
    setting. Due to the complexity of analyzing optimization in such a relaxed setting,
    this line of work often assumes \emph{global} communication rounds, which require
    additional synchronization. In this paper, we consider decentralized optimization
    in the simpler, but harder to analyze, \emph{asynchronous gossip} model, in which
    communication occurs in discrete, randomly chosen pairings among nodes. Perhaps
    surprisingly, we show that a variant of SGD called \emph{SwarmSGD} still converges
    in this setting, even if \emph{non-blocking communication}, \emph{quantization},
    and \emph{local steps} are all applied \emph{in conjunction}, and even if the
    node data distributions and underlying graph topology are both \emph{heterogenous}.
    Our analysis is based on a new connection with multi-dimensional load-balancing
    processes. We implement this algorithm and deploy it in a super-computing environment,
    showing that it can outperform previous decentralized methods in terms of end-to-end
    training time, and that it can even rival carefully-tuned large-batch SGD for
    certain tasks.
acknowledgement: "We gratefully acknowledge funding from the European Research Council
  (ERC) under the European Union’s Horizon 2020 research and innovation programme
  (grant agreement No 805223 ScaleML). PD partly conducted this work while at IST
  Austria and was supported by the European Union’s Horizon 2020 programme under the
  Marie Skłodowska-Curie grant agreement No. 754411. SL was funded in part by European
  Research Council (ERC) under the European Union’s Horizon 2020 programme (grant
  agreement DAPP, No. 678880, and EPiGRAM-HS, No. 801039).\r\n"
article_processing_charge: No
arxiv: 1
author:
- first_name: Giorgi
  full_name: Nadiradze, Giorgi
  id: 3279A00C-F248-11E8-B48F-1D18A9856A87
  last_name: Nadiradze
  orcid: 0000-0001-5634-0731
- first_name: Amirmojtaba
  full_name: Sabour, Amirmojtaba
  id: bcc145fd-e77f-11ea-ae8b-80d661dbff67
  last_name: Sabour
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
- first_name: Shigang
  full_name: Li, Shigang
  last_name: Li
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
citation:
  ama: 'Nadiradze G, Sabour A, Davies P, Li S, Alistarh D-A. Asynchronous decentralized
    SGD with quantized and local updates. In: <i>35th Conference on Neural Information
    Processing Systems</i>. Neural Information Processing Systems Foundation; 2021.'
  apa: 'Nadiradze, G., Sabour, A., Davies, P., Li, S., &#38; Alistarh, D.-A. (2021).
    Asynchronous decentralized SGD with quantized and local updates. In <i>35th Conference
    on Neural Information Processing Systems</i>. Sydney, Australia: Neural Information
    Processing Systems Foundation.'
  chicago: Nadiradze, Giorgi, Amirmojtaba Sabour, Peter Davies, Shigang Li, and Dan-Adrian
    Alistarh. “Asynchronous Decentralized SGD with Quantized and Local Updates.” In
    <i>35th Conference on Neural Information Processing Systems</i>. Neural Information
    Processing Systems Foundation, 2021.
  ieee: G. Nadiradze, A. Sabour, P. Davies, S. Li, and D.-A. Alistarh, “Asynchronous
    decentralized SGD with quantized and local updates,” in <i>35th Conference on
    Neural Information Processing Systems</i>, Sydney, Australia, 2021.
  ista: 'Nadiradze G, Sabour A, Davies P, Li S, Alistarh D-A. 2021. Asynchronous decentralized
    SGD with quantized and local updates. 35th Conference on Neural Information Processing
    Systems. NeurIPS: Neural Information Processing Systems.'
  mla: Nadiradze, Giorgi, et al. “Asynchronous Decentralized SGD with Quantized and
    Local Updates.” <i>35th Conference on Neural Information Processing Systems</i>,
    Neural Information Processing Systems Foundation, 2021.
  short: G. Nadiradze, A. Sabour, P. Davies, S. Li, D.-A. Alistarh, in:, 35th Conference
    on Neural Information Processing Systems, Neural Information Processing Systems
    Foundation, 2021.
conference:
  end_date: 2021-12-14
  location: Sydney, Australia
  name: 'NeurIPS: Neural Information Processing Systems'
  start_date: 2021-12-06
date_created: 2021-12-09T10:59:12Z
date_published: 2021-12-01T00:00:00Z
date_updated: 2026-06-18T08:41:40Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '1910.12308'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://papers.nips.cc/paper/2021/hash/362c99307cdc3f2d8b410652386a9dd1-Abstract.html
month: '12'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: 35th Conference on Neural Information Processing Systems
publication_status: published
publisher: Neural Information Processing Systems Foundation
quality_controlled: '1'
related_material:
  record:
  - id: '10429'
    relation: dissertation_contains
    status: public
status: public
title: Asynchronous decentralized SGD with quantized and local updates
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2021'
...
---
_id: '7939'
abstract:
- lang: eng
  text: "We design fast deterministic algorithms for distance computation in the Congested
    Clique model. Our key contributions include:\r\n    A (2+ϵ)-approximation for
    all-pairs shortest paths in O(log2n/ϵ) rounds on unweighted undirected graphs.
    With a small additional additive factor, this also applies for weighted graphs.
    This is the first sub-polynomial constant-factor approximation for APSP in this
    model.\r\n    A (1+ϵ)-approximation for multi-source shortest paths from O(n−−√)
    sources in O(log2n/ϵ) rounds on weighted undirected graphs. This is the first
    sub-polynomial algorithm obtaining this approximation for a set of sources of
    polynomial size.\r\n\r\nOur main techniques are new distance tools that are obtained
    via improved algorithms for sparse matrix multiplication, which we leverage to
    construct efficient hopsets and shortest paths. Furthermore, our techniques extend
    to additional distance problems for which we improve upon the state-of-the-art,
    including diameter approximation, and an exact single-source shortest paths algorithm
    for weighted undirected graphs in O~(n1/6) rounds. "
acknowledgement: Open access funding provided by Institute of Science and Technology
  (IST Austria). We thank Mohsen Ghaffari, Michael Elkin and Merav Parter for fruitful
  discussions. This project has received funding from the European Union’s Horizon
  2020 Research And Innovation Program under Grant Agreement No. 755839.
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Keren
  full_name: Censor-Hillel, Keren
  last_name: Censor-Hillel
- first_name: Michal
  full_name: Dory, Michal
  last_name: Dory
- first_name: Janne
  full_name: Korhonen, Janne
  id: C5402D42-15BC-11E9-A202-CA2BE6697425
  last_name: Korhonen
- first_name: Dean
  full_name: Leitersdorf, Dean
  last_name: Leitersdorf
citation:
  ama: Censor-Hillel K, Dory M, Korhonen J, Leitersdorf D. Fast approximate shortest
    paths in the congested clique. <i>Distributed Computing</i>. 2021;34:463-487.
    doi:<a href="https://doi.org/10.1007/s00446-020-00380-5">10.1007/s00446-020-00380-5</a>
  apa: Censor-Hillel, K., Dory, M., Korhonen, J., &#38; Leitersdorf, D. (2021). Fast
    approximate shortest paths in the congested clique. <i>Distributed Computing</i>.
    Springer Nature. <a href="https://doi.org/10.1007/s00446-020-00380-5">https://doi.org/10.1007/s00446-020-00380-5</a>
  chicago: Censor-Hillel, Keren, Michal Dory, Janne Korhonen, and Dean Leitersdorf.
    “Fast Approximate Shortest Paths in the Congested Clique.” <i>Distributed Computing</i>.
    Springer Nature, 2021. <a href="https://doi.org/10.1007/s00446-020-00380-5">https://doi.org/10.1007/s00446-020-00380-5</a>.
  ieee: K. Censor-Hillel, M. Dory, J. Korhonen, and D. Leitersdorf, “Fast approximate
    shortest paths in the congested clique,” <i>Distributed Computing</i>, vol. 34.
    Springer Nature, pp. 463–487, 2021.
  ista: Censor-Hillel K, Dory M, Korhonen J, Leitersdorf D. 2021. Fast approximate
    shortest paths in the congested clique. Distributed Computing. 34, 463–487.
  mla: Censor-Hillel, Keren, et al. “Fast Approximate Shortest Paths in the Congested
    Clique.” <i>Distributed Computing</i>, vol. 34, Springer Nature, 2021, pp. 463–87,
    doi:<a href="https://doi.org/10.1007/s00446-020-00380-5">10.1007/s00446-020-00380-5</a>.
  short: K. Censor-Hillel, M. Dory, J. Korhonen, D. Leitersdorf, Distributed Computing
    34 (2021) 463–487.
corr_author: '1'
date_created: 2020-06-07T22:00:54Z
date_published: 2021-12-01T00:00:00Z
date_updated: 2026-06-18T19:28:41Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.1007/s00446-020-00380-5
external_id:
  arxiv:
  - '1903.05956'
  isi:
  - '000556444600001'
intvolume: '        34'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1007/s00446-020-00380-5
month: '12'
oa: 1
oa_version: Published Version
page: 463-487
project:
- _id: B67AFEDC-15C9-11EA-A837-991A96BB2854
  name: IST Austria Open Access Fund
publication: Distributed Computing
publication_identifier:
  eissn:
  - 1432-0452
  issn:
  - 0178-2770
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  record:
  - id: '6933'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Fast approximate shortest paths in the congested clique
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2021'
...
---
_id: '8723'
abstract:
- lang: eng
  text: Deep learning at scale is dominated by communication time. Distributing samples
    across nodes usually yields the best performance, but poses scaling challenges
    due to global information dissemination and load imbalance across uneven sample
    lengths. State-of-the-art decentralized optimizers mitigate the problem, but require
    more iterations to achieve the same accuracy as their globally-communicating counterparts.
    We present Wait-Avoiding Group Model Averaging (WAGMA) SGD, a wait-avoiding stochastic
    optimizer that reduces global communication via subgroup weight exchange. The
    key insight is a combination of algorithmic changes to the averaging scheme and
    the use of a group allreduce operation. We prove the convergence of WAGMA-SGD,
    and empirically show that it retains convergence rates similar to Allreduce-SGD.
    For evaluation, we train ResNet-50 on ImageNet; Transformer for machine translation;
    and deep reinforcement learning for navigation at scale. Compared with state-of-the-art
    decentralized SGD variants, WAGMA-SGD significantly improves training throughput
    (e.g., 2.1× on 1,024 GPUs for reinforcement learning), and achieves the fastest
    time-to-solution (e.g., the highest score using the shortest training time for
    Transformer).
acknowledgement: "This project has received funding from the European Research Council
  (ERC) under the European Union’s Hori-\r\nzon 2020 programme under Grant DAPP, Grant
  678880; EPi-GRAM-HS, Grant 801039; and ERC Starting Grant ScaleML, Grant 805223.
  The work of Tal Ben-Nun is supported by the Swiss National Science Foundation (Ambizione
  Project No. 185778). The work of Nikoli Dryden is supported by the ETH Postdoctoral
  Fellowship. The authors would like to thank the Swiss National Supercomputing Center
  for providing the computing resources and technical support."
article_number: '9271898'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Shigang
  full_name: Li, Shigang
  last_name: Li
- first_name: Tal Ben-Nun
  full_name: Tal Ben-Nun, Tal Ben-Nun
  last_name: Tal Ben-Nun
- first_name: Giorgi
  full_name: Nadiradze, Giorgi
  id: 3279A00C-F248-11E8-B48F-1D18A9856A87
  last_name: Nadiradze
  orcid: 0000-0001-5634-0731
- first_name: Salvatore Di
  full_name: Girolamo, Salvatore Di
  last_name: Girolamo
- first_name: Nikoli
  full_name: Dryden, Nikoli
  last_name: Dryden
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Torsten
  full_name: Hoefler, Torsten
  last_name: Hoefler
citation:
  ama: Li S, Tal Ben-Nun TB-N, Nadiradze G, et al. Breaking (global) barriers in parallel
    stochastic optimization with wait-avoiding group averaging. <i>IEEE Transactions
    on Parallel and Distributed Systems</i>. 2021;32(7). doi:<a href="https://doi.org/10.1109/TPDS.2020.3040606">10.1109/TPDS.2020.3040606</a>
  apa: Li, S., Tal Ben-Nun, T. B.-N., Nadiradze, G., Girolamo, S. D., Dryden, N.,
    Alistarh, D.-A., &#38; Hoefler, T. (2021). Breaking (global) barriers in parallel
    stochastic optimization with wait-avoiding group averaging. <i>IEEE Transactions
    on Parallel and Distributed Systems</i>. IEEE. <a href="https://doi.org/10.1109/TPDS.2020.3040606">https://doi.org/10.1109/TPDS.2020.3040606</a>
  chicago: Li, Shigang, Tal Ben-Nun Tal Ben-Nun, Giorgi Nadiradze, Salvatore Di Girolamo,
    Nikoli Dryden, Dan-Adrian Alistarh, and Torsten Hoefler. “Breaking (Global) Barriers
    in Parallel Stochastic Optimization with Wait-Avoiding Group Averaging.” <i>IEEE
    Transactions on Parallel and Distributed Systems</i>. IEEE, 2021. <a href="https://doi.org/10.1109/TPDS.2020.3040606">https://doi.org/10.1109/TPDS.2020.3040606</a>.
  ieee: S. Li <i>et al.</i>, “Breaking (global) barriers in parallel stochastic optimization
    with wait-avoiding group averaging,” <i>IEEE Transactions on Parallel and Distributed
    Systems</i>, vol. 32, no. 7. IEEE, 2021.
  ista: Li S, Tal Ben-Nun TB-N, Nadiradze G, Girolamo SD, Dryden N, Alistarh D-A,
    Hoefler T. 2021. Breaking (global) barriers in parallel stochastic optimization
    with wait-avoiding group averaging. IEEE Transactions on Parallel and Distributed
    Systems. 32(7), 9271898.
  mla: Li, Shigang, et al. “Breaking (Global) Barriers in Parallel Stochastic Optimization
    with Wait-Avoiding Group Averaging.” <i>IEEE Transactions on Parallel and Distributed
    Systems</i>, vol. 32, no. 7, 9271898, IEEE, 2021, doi:<a href="https://doi.org/10.1109/TPDS.2020.3040606">10.1109/TPDS.2020.3040606</a>.
  short: S. Li, T.B.-N. Tal Ben-Nun, G. Nadiradze, S.D. Girolamo, N. Dryden, D.-A.
    Alistarh, T. Hoefler, IEEE Transactions on Parallel and Distributed Systems 32
    (2021).
date_created: 2020-11-05T15:25:43Z
date_published: 2021-07-01T00:00:00Z
date_updated: 2025-07-10T12:01:23Z
day: '01'
department:
- _id: DaAl
doi: 10.1109/TPDS.2020.3040606
ec_funded: 1
external_id:
  arxiv:
  - '2005.00124'
  isi:
  - '000621405200019'
intvolume: '        32'
isi: 1
issue: '7'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2005.00124
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: 268A44D6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '805223'
  name: Elastic Coordination for Scalable Machine Learning
publication: IEEE Transactions on Parallel and Distributed Systems
publication_identifier:
  issn:
  - 1045-9219
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: Breaking (global) barriers in parallel stochastic optimization with wait-avoiding
  group averaging
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 32
year: '2021'
...
---
_id: '9541'
abstract:
- lang: eng
  text: The Massively Parallel Computation (MPC) model is an emerging model that distills
    core aspects of distributed and parallel computation, developed as a tool to solve
    combinatorial (typically graph) problems in systems of many machines with limited
    space. Recent work has focused on the regime in which machines have sublinear
    (in n, the number of nodes in the input graph) space, with randomized algorithms
    presented for the fundamental problems of Maximal Matching and Maximal Independent
    Set. However, there have been no prior corresponding deterministic algorithms.
    A major challenge underlying the sublinear space setting is that the local space
    of each machine might be too small to store all edges incident to a single node.
    This poses a considerable obstacle compared to classical models in which each
    node is assumed to know and have easy access to its incident edges. To overcome
    this barrier, we introduce a new graph sparsification technique that deterministically
    computes a low-degree subgraph, with the additional property that solving the
    problem on this subgraph provides significant progress towards solving the problem
    for the original input graph. Using this framework to derandomize the well-known
    algorithm of Luby [SICOMP’86], we obtain O(log Δ + log log n)-round deterministic
    MPC algorithms for solving the problems of Maximal Matching and Maximal Independent
    Set with O(nɛ) space on each machine for any constant ɛ > 0. These algorithms
    also run in O(log Δ) rounds in the closely related model of CONGESTED CLIQUE,
    improving upon the state-of-the-art bound of O(log 2Δ) rounds by Censor-Hillel
    et al. [DISC’17].
acknowledgement: "Institute of Science and Technology Austria (IST Austria). Email:
  peter.davies@ist.ac.at. Work partially\r\ndone at the Department of Computer Science
  and Centre for Discrete Mathematics and its Applications (DIMAP),University of Warwick.
  Research partially supported by the European Union’s Horizon 2020 research and innovation
  programme under the Marie Skłodowska-Curie grant agreement No 754411, the Centre
  for Discrete Mathematics and its Applications, a Weizmann-UK Making Connections
  Grant, and EPSRC award EP/N011163/1."
article_number: '16'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Artur
  full_name: Czumaj, Artur
  last_name: Czumaj
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
- first_name: Merav
  full_name: Parter, Merav
  last_name: Parter
citation:
  ama: Czumaj A, Davies P, Parter M. Graph sparsification for derandomizing massively
    parallel computation with low space. <i>ACM Transactions on Algorithms</i>. 2021;17(2).
    doi:<a href="https://doi.org/10.1145/3451992">10.1145/3451992</a>
  apa: Czumaj, A., Davies, P., &#38; Parter, M. (2021). Graph sparsification for derandomizing
    massively parallel computation with low space. <i>ACM Transactions on Algorithms</i>.
    Association for Computing Machinery. <a href="https://doi.org/10.1145/3451992">https://doi.org/10.1145/3451992</a>
  chicago: Czumaj, Artur, Peter Davies, and Merav Parter. “Graph Sparsification for
    Derandomizing Massively Parallel Computation with Low Space.” <i>ACM Transactions
    on Algorithms</i>. Association for Computing Machinery, 2021. <a href="https://doi.org/10.1145/3451992">https://doi.org/10.1145/3451992</a>.
  ieee: A. Czumaj, P. Davies, and M. Parter, “Graph sparsification for derandomizing
    massively parallel computation with low space,” <i>ACM Transactions on Algorithms</i>,
    vol. 17, no. 2. Association for Computing Machinery, 2021.
  ista: Czumaj A, Davies P, Parter M. 2021. Graph sparsification for derandomizing
    massively parallel computation with low space. ACM Transactions on Algorithms.
    17(2), 16.
  mla: Czumaj, Artur, et al. “Graph Sparsification for Derandomizing Massively Parallel
    Computation with Low Space.” <i>ACM Transactions on Algorithms</i>, vol. 17, no.
    2, 16, Association for Computing Machinery, 2021, doi:<a href="https://doi.org/10.1145/3451992">10.1145/3451992</a>.
  short: A. Czumaj, P. Davies, M. Parter, ACM Transactions on Algorithms 17 (2021).
date_created: 2021-06-10T19:31:05Z
date_published: 2021-06-01T00:00:00Z
date_updated: 2025-04-15T06:54:47Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.1145/3451992
ec_funded: 1
external_id:
  arxiv:
  - '1912.05390'
  isi:
  - '000661311300006'
file:
- access_level: open_access
  checksum: a21c627683890c309a68f6389302c408
  content_type: application/pdf
  creator: pdavies
  date_created: 2021-06-10T19:33:56Z
  date_updated: 2021-06-10T19:33:56Z
  file_id: '9542'
  file_name: MISMM-arxiv.pdf
  file_size: 587404
  relation: main_file
  success: 1
file_date_updated: 2021-06-10T19:33:56Z
has_accepted_license: '1'
intvolume: '        17'
isi: 1
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1912.05390
month: '06'
oa: 1
oa_version: Submitted Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: ACM Transactions on Algorithms
publication_identifier:
  eissn:
  - 1549-6333
  issn:
  - 1549-6325
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
related_material:
  record:
  - id: '7802'
    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: Graph sparsification for derandomizing massively parallel computation with
  low space
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 17
year: '2021'
...
---
_id: '9543'
abstract:
- lang: eng
  text: We consider the problem ofdistributed mean estimation (DME), in which n machines
    are each given a local d-dimensional vector xv∈Rd, and must cooperate to estimate
    the mean of their inputs μ=1n∑nv=1xv, while minimizing total communication cost.
    DME is a fundamental construct in distributed machine learning, and there has
    been considerable work on variants of this problem, especially in the context
    of distributed variance reduction for stochastic gradients in parallel SGD. Previous
    work typically assumes an upper bound on the norm of the input vectors, and achieves
    an error bound in terms of this norm. However, in many real applications, the
    input vectors are concentrated around the correct output μ, but μ itself has large
    norm. In such cases, previous output error bounds perform poorly. In this paper,
    we show that output error bounds need not depend on input norm. We provide a method
    of quantization which allows distributed mean estimation to be performed with
    solution quality dependent only on the distance between inputs, not on input norm,
    and show an analogous result for distributed variance reduction. The technique
    is based on a new connection with lattice theory. We also provide lower bounds
    showing that the communication to error trade-off of our algorithms is asymptotically
    optimal. As the lattices achieving optimal bounds under l2-norm can be computationally
    impractical, we also present an extension which leverages easy-to-use cubic lattices,
    and is loose only up to a logarithmic factor ind. We show experimentally that
    our method yields practical improvements for common applications, relative to
    prior approaches.
article_processing_charge: No
arxiv: 1
author:
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
- first_name: Vijaykrishna
  full_name: Gurunanthan, Vijaykrishna
  last_name: Gurunanthan
- first_name: 'Niusha '
  full_name: 'Moshrefi, Niusha '
  id: 4db776ff-ce15-11eb-96e3-bc2b90b01c16
  last_name: Moshrefi
- first_name: Saleh
  full_name: Ashkboos, Saleh
  id: 0D0A9058-257B-11EA-A937-9341C3D8BC8A
  last_name: Ashkboos
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
citation:
  ama: 'Davies P, Gurunanthan V, Moshrefi N, Ashkboos S, Alistarh D-A. New bounds
    for distributed mean estimation and variance reduction. In: <i>9th International
    Conference on Learning Representations</i>. ; 2021.'
  apa: Davies, P., Gurunanthan, V., Moshrefi, N., Ashkboos, S., &#38; Alistarh, D.-A.
    (2021). New bounds for distributed mean estimation and variance reduction. In
    <i>9th International Conference on Learning Representations</i>. Virtual.
  chicago: Davies, Peter, Vijaykrishna Gurunanthan, Niusha  Moshrefi, Saleh Ashkboos,
    and Dan-Adrian Alistarh. “New Bounds for Distributed Mean Estimation and Variance
    Reduction.” In <i>9th International Conference on Learning Representations</i>,
    2021.
  ieee: P. Davies, V. Gurunanthan, N. Moshrefi, S. Ashkboos, and D.-A. Alistarh, “New
    bounds for distributed mean estimation and variance reduction,” in <i>9th International
    Conference on Learning Representations</i>, Virtual, 2021.
  ista: 'Davies P, Gurunanthan V, Moshrefi N, Ashkboos S, Alistarh D-A. 2021. New
    bounds for distributed mean estimation and variance reduction. 9th International
    Conference on Learning Representations. ICLR: International Conference on Learning
    Representations.'
  mla: Davies, Peter, et al. “New Bounds for Distributed Mean Estimation and Variance
    Reduction.” <i>9th International Conference on Learning Representations</i>, 2021.
  short: P. Davies, V. Gurunanthan, N. Moshrefi, S. Ashkboos, D.-A. Alistarh, in:,
    9th International Conference on Learning Representations, 2021.
conference:
  end_date: 2021-05-07
  location: Virtual
  name: 'ICLR: International Conference on Learning Representations'
  start_date: 2021-05-03
corr_author: '1'
date_created: 2021-06-10T19:46:08Z
date_published: 2021-05-01T00:00:00Z
date_updated: 2026-06-18T19:53:18Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
ec_funded: 1
external_id:
  arxiv:
  - '2002.09268'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://openreview.net/pdf?id=t86MwoUCCNe
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: 9th International Conference on Learning Representations
publication_status: published
quality_controlled: '1'
status: public
title: New bounds for distributed mean estimation and variance reduction
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2021'
...
---
_id: '9571'
abstract:
- lang: eng
  text: As the size and complexity of models and datasets grow, so does the need for
    communication-efficient variants of stochastic gradient descent that can be deployed
    to perform parallel model training. One popular communication-compression method
    for data-parallel SGD is QSGD (Alistarh et al., 2017), which quantizes and encodes
    gradients to reduce communication costs. The baseline variant of QSGD provides
    strong theoretical guarantees, however, for practical purposes, the authors proposed
    a heuristic variant which we call QSGDinf, which demonstrated impressive empirical
    gains for distributed training of large neural networks. In this paper, we build
    on this work to propose a new gradient quantization scheme, and show that it has
    both stronger theoretical guarantees than QSGD, and matches and exceeds the empirical
    performance of the QSGDinf heuristic and of other compression methods.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Ali
  full_name: Ramezani-Kebrya, Ali
  last_name: Ramezani-Kebrya
- first_name: Fartash
  full_name: Faghri, Fartash
  last_name: Faghri
- first_name: Ilya
  full_name: Markov, Ilya
  last_name: Markov
- first_name: Vitalii
  full_name: Aksenov, Vitalii
  id: 2980135A-F248-11E8-B48F-1D18A9856A87
  last_name: Aksenov
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Daniel M.
  full_name: Roy, Daniel M.
  last_name: Roy
citation:
  ama: 'Ramezani-Kebrya A, Faghri F, Markov I, Aksenov V, Alistarh D-A, Roy DM. NUQSGD:
    Provably communication-efficient data-parallel SGD via nonuniform quantization.
    <i>Journal of Machine Learning Research</i>. 2021;22(114):1−43.'
  apa: 'Ramezani-Kebrya, A., Faghri, F., Markov, I., Aksenov, V., Alistarh, D.-A.,
    &#38; Roy, D. M. (2021). NUQSGD: Provably communication-efficient data-parallel
    SGD via nonuniform quantization. <i>Journal of Machine Learning Research</i>.
    Journal of Machine Learning Research.'
  chicago: 'Ramezani-Kebrya, Ali, Fartash Faghri, Ilya Markov, Vitalii Aksenov, Dan-Adrian
    Alistarh, and Daniel M. Roy. “NUQSGD: Provably Communication-Efficient Data-Parallel
    SGD via Nonuniform Quantization.” <i>Journal of Machine Learning Research</i>.
    Journal of Machine Learning Research, 2021.'
  ieee: 'A. Ramezani-Kebrya, F. Faghri, I. Markov, V. Aksenov, D.-A. Alistarh, and
    D. M. Roy, “NUQSGD: Provably communication-efficient data-parallel SGD via nonuniform
    quantization,” <i>Journal of Machine Learning Research</i>, vol. 22, no. 114.
    Journal of Machine Learning Research, p. 1−43, 2021.'
  ista: 'Ramezani-Kebrya A, Faghri F, Markov I, Aksenov V, Alistarh D-A, Roy DM. 2021.
    NUQSGD: Provably communication-efficient data-parallel SGD via nonuniform quantization.
    Journal of Machine Learning Research. 22(114), 1−43.'
  mla: 'Ramezani-Kebrya, Ali, et al. “NUQSGD: Provably Communication-Efficient Data-Parallel
    SGD via Nonuniform Quantization.” <i>Journal of Machine Learning Research</i>,
    vol. 22, no. 114, Journal of Machine Learning Research, 2021, p. 1−43.'
  short: A. Ramezani-Kebrya, F. Faghri, I. Markov, V. Aksenov, D.-A. Alistarh, D.M.
    Roy, Journal of Machine Learning Research 22 (2021) 1−43.
corr_author: '1'
date_created: 2021-06-20T22:01:33Z
date_published: 2021-04-01T00:00:00Z
date_updated: 2025-07-10T12:01:54Z
day: '01'
ddc:
- '000'
department:
- _id: DaAl
external_id:
  arxiv:
  - '1908.06077'
file:
- access_level: open_access
  checksum: 6428aa8bcb67768b6949c99b55d5281d
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  creator: asandaue
  date_created: 2021-06-23T07:09:41Z
  date_updated: 2021-06-23T07:09:41Z
  file_id: '9595'
  file_name: 2021_JournalOfMachineLearningResearch_Ramezani-Kebrya.pdf
  file_size: 11237154
  relation: main_file
  success: 1
file_date_updated: 2021-06-23T07:09:41Z
has_accepted_license: '1'
intvolume: '        22'
issue: '114'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.jmlr.org/papers/v22/20-255.html
month: '04'
oa: 1
oa_version: Published Version
page: 1−43
publication: Journal of Machine Learning Research
publication_identifier:
  eissn:
  - 1533-7928
  issn:
  - 1532-4435
publication_status: published
publisher: Journal of Machine Learning Research
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'NUQSGD: Provably communication-efficient data-parallel SGD via nonuniform
  quantization'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 22
year: '2021'
...
---
_id: '9620'
abstract:
- lang: eng
  text: "In this note, we introduce a distributed twist on the classic coupon collector
    problem: a set of m collectors wish to each obtain a set of n coupons; for this,
    they can each sample coupons uniformly at random, but can also meet in pairwise
    interactions, during which they can exchange coupons. By doing so, they hope to
    reduce the number of coupons that must be sampled by each collector in order to
    obtain a full set. This extension is natural when considering real-world manifestations
    of the coupon collector phenomenon, and has been remarked upon and studied empirically
    (Hayes and Hannigan 2006, Ahmad et al. 2014, Delmarcelle 2019).\r\n\r\nWe provide
    the first theoretical analysis for such a scenario. We find that “coupon collecting
    with friends” can indeed significantly reduce the number of coupons each collector
    must sample, and raises interesting connections to the more traditional variants
    of the problem. While our analysis is in most cases asymptotically tight, there
    are several open questions raised, regarding finer-grained analysis of both “coupon
    collecting with friends,” and of a long-studied variant of the original problem
    in which a collector requires multiple full sets of coupons."
acknowledgement: Peter Davies is supported by the European Union’s Horizon2020 research
  and innovation programme under the Marie Skłodowska-Curie grant agreement No. 754411.
alternative_title:
- LNCS
article_processing_charge: No
author:
- first_name: Dan-Adrian
  full_name: Alistarh, Dan-Adrian
  id: 4A899BFC-F248-11E8-B48F-1D18A9856A87
  last_name: Alistarh
  orcid: 0000-0003-3650-940X
- first_name: Peter
  full_name: Davies, Peter
  id: 11396234-BB50-11E9-B24C-90FCE5697425
  last_name: Davies
  orcid: 0000-0002-5646-9524
citation:
  ama: 'Alistarh D-A, Davies P. Collecting coupons is faster with friends. In: <i>Structural
    Information and Communication Complexity</i>. Vol 12810. Springer Nature; 2021:3-12.
    doi:<a href="https://doi.org/10.1007/978-3-030-79527-6_1">10.1007/978-3-030-79527-6_1</a>'
  apa: 'Alistarh, D.-A., &#38; Davies, P. (2021). Collecting coupons is faster with
    friends. In <i>Structural Information and Communication Complexity</i> (Vol. 12810,
    pp. 3–12). Wrocław, Poland: Springer Nature. <a href="https://doi.org/10.1007/978-3-030-79527-6_1">https://doi.org/10.1007/978-3-030-79527-6_1</a>'
  chicago: Alistarh, Dan-Adrian, and Peter Davies. “Collecting Coupons Is Faster with
    Friends.” In <i>Structural Information and Communication Complexity</i>, 12810:3–12.
    Springer Nature, 2021. <a href="https://doi.org/10.1007/978-3-030-79527-6_1">https://doi.org/10.1007/978-3-030-79527-6_1</a>.
  ieee: D.-A. Alistarh and P. Davies, “Collecting coupons is faster with friends,”
    in <i>Structural Information and Communication Complexity</i>, Wrocław, Poland,
    2021, vol. 12810, pp. 3–12.
  ista: 'Alistarh D-A, Davies P. 2021. Collecting coupons is faster with friends.
    Structural Information and Communication Complexity. SIROCCO: International Colloquium
    on Structural Information and Communication Complexity, LNCS, vol. 12810, 3–12.'
  mla: Alistarh, Dan-Adrian, and Peter Davies. “Collecting Coupons Is Faster with
    Friends.” <i>Structural Information and Communication Complexity</i>, vol. 12810,
    Springer Nature, 2021, pp. 3–12, doi:<a href="https://doi.org/10.1007/978-3-030-79527-6_1">10.1007/978-3-030-79527-6_1</a>.
  short: D.-A. Alistarh, P. Davies, in:, Structural Information and Communication
    Complexity, Springer Nature, 2021, pp. 3–12.
conference:
  end_date: 2021-07-01
  location: Wrocław, Poland
  name: 'SIROCCO: International Colloquium on Structural Information and Communication
    Complexity'
  start_date: 2021-06-28
date_created: 2021-07-01T11:04:43Z
date_published: 2021-06-20T00:00:00Z
date_updated: 2025-09-10T10:04:46Z
day: '20'
ddc:
- '000'
department:
- _id: DaAl
doi: 10.1007/978-3-030-79527-6_1
ec_funded: 1
external_id:
  isi:
  - '001292788400001'
file:
- access_level: open_access
  checksum: fe37fb9af3f5016c1084af9d6e7109bd
  content_type: application/pdf
  creator: pdavies
  date_created: 2021-07-01T11:21:40Z
  date_updated: 2021-07-01T11:21:40Z
  file_id: '9621'
  file_name: Population_Coupon_Collector.pdf
  file_size: 319728
  relation: main_file
file_date_updated: 2021-07-01T11:21:40Z
has_accepted_license: '1'
intvolume: '     12810'
isi: 1
language:
- iso: eng
month: '06'
oa: 1
oa_version: Preprint
page: 3-12
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Structural Information and Communication Complexity
publication_identifier:
  eisbn:
  - '9783030795276'
  eissn:
  - 1611-3349
  isbn:
  - '9783030795269'
  issn:
  - 0302-9743
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Collecting coupons is faster with friends
type: conference
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 12810
year: '2021'
...
