7 Search Results for "Kallimanis, Nikolaos D."


Document
Recoverable Lock-Free Locks

Authors: Hagit Attiya, Panagiota Fatourou, Eleftherios Kosmas, and Yuanhao Wei

Published in: LIPIcs, Volume 361, 29th International Conference on Principles of Distributed Systems (OPODIS 2025)


Abstract
This paper presents the first transformation that introduces both lock-freedom and recoverability. Our transformation starts with a lock-based implementation, and provides a recoverable, lock-free substitution to lock acquire and lock release operations. The transformation supports nested locks for generality and ensures recoverability without jeopardising the correctness of the lock-based implementation it is applied on.

Cite as

Hagit Attiya, Panagiota Fatourou, Eleftherios Kosmas, and Yuanhao Wei. Recoverable Lock-Free Locks. In 29th International Conference on Principles of Distributed Systems (OPODIS 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 361, pp. 17:1-17:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)


Copy BibTex To Clipboard

@InProceedings{attiya_et_al:LIPIcs.OPODIS.2025.17,
  author =	{Attiya, Hagit and Fatourou, Panagiota and Kosmas, Eleftherios and Wei, Yuanhao},
  title =	{{Recoverable Lock-Free Locks}},
  booktitle =	{29th International Conference on Principles of Distributed Systems (OPODIS 2025)},
  pages =	{17:1--17:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-409-3},
  ISSN =	{1868-8969},
  year =	{2026},
  volume =	{361},
  editor =	{Arusoaie, Andrei and Onica, Emanuel and Spear, Michael and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2025.17},
  URN =		{urn:nbn:de:0030-drops-251905},
  doi =		{10.4230/LIPIcs.OPODIS.2025.17},
  annote =	{Keywords: recoverable computing, NVM, lock, lock-freedom}
}
Document
PIPQ: Strict Insert-Optimized Concurrent Priority Queue

Authors: Olivia Grimes, Ahmed Hassan, Panagiota Fatourou, and Roberto Palmieri

Published in: LIPIcs, Volume 356, 39th International Symposium on Distributed Computing (DISC 2025)


Abstract
This paper presents PIPQ, a strict and linearizable concurrent priority queue whose design differs from existing solutions in literature because it focuses on enabling parallelism of insert operations as opposed to accelerating delete-min operations, as traditionally done. In a nutshell, PIPQ’s structure includes two levels: the worker level and the leader level. The worker level provides per-thread data structures enabling fast and parallel insertions. The leader level contains the highest priority elements in the priority queue and can thus serve delete-min operations. Our evaluation, which includes an exploration of different data access patterns, operation mixes, runtime settings, and an integration into a graph-based application, shows that PIPQ outperforms competitors in a variety of cases, especially with insert-dominant workloads.

Cite as

Olivia Grimes, Ahmed Hassan, Panagiota Fatourou, and Roberto Palmieri. PIPQ: Strict Insert-Optimized Concurrent Priority Queue. In 39th International Symposium on Distributed Computing (DISC 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 356, pp. 35:1-35:23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)


Copy BibTex To Clipboard

@InProceedings{grimes_et_al:LIPIcs.DISC.2025.35,
  author =	{Grimes, Olivia and Hassan, Ahmed and Fatourou, Panagiota and Palmieri, Roberto},
  title =	{{PIPQ: Strict Insert-Optimized Concurrent Priority Queue}},
  booktitle =	{39th International Symposium on Distributed Computing (DISC 2025)},
  pages =	{35:1--35:23},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-402-4},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{356},
  editor =	{Kowalski, Dariusz R.},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2025.35},
  URN =		{urn:nbn:de:0030-drops-248525},
  doi =		{10.4230/LIPIcs.DISC.2025.35},
  annote =	{Keywords: Priority Queue, Concurrent Data Structures, Synchronization}
}
Document
Brief Announcement
Brief Announcement: Concurrent Double-Ended Priority Queues

Authors: Panagiota Fatourou, Eric Ruppert, and Ioannis Xiradakis

Published in: LIPIcs, Volume 356, 39th International Symposium on Distributed Computing (DISC 2025)


Abstract
This work provides the first concurrent implementation of a double-ended priority queue (DEPQ). We describe a general way to add an ExtractMax operation to any concurrent priority queue that already supports Insert and ExtractMin.

Cite as

Panagiota Fatourou, Eric Ruppert, and Ioannis Xiradakis. Brief Announcement: Concurrent Double-Ended Priority Queues. In 39th International Symposium on Distributed Computing (DISC 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 356, pp. 55:1-55:7, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)


Copy BibTex To Clipboard

@InProceedings{fatourou_et_al:LIPIcs.DISC.2025.55,
  author =	{Fatourou, Panagiota and Ruppert, Eric and Xiradakis, Ioannis},
  title =	{{Brief Announcement: Concurrent Double-Ended Priority Queues}},
  booktitle =	{39th International Symposium on Distributed Computing (DISC 2025)},
  pages =	{55:1--55:7},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-402-4},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{356},
  editor =	{Kowalski, Dariusz R.},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2025.55},
  URN =		{urn:nbn:de:0030-drops-248719},
  doi =		{10.4230/LIPIcs.DISC.2025.55},
  annote =	{Keywords: shared-memory, data structure, double-ended, priority queue, priority deque, heap, skip list, combining}
}
Document
Brief Announcement
Brief Announcement: Persistent Software Combining

Authors: Panagiota Fatourou, Nikolaos D. Kallimanis, and Eleftherios Kosmas

Published in: LIPIcs, Volume 209, 35th International Symposium on Distributed Computing (DISC 2021)


Abstract
We study the performance power of software combining in designing recoverable algorithms and data structures. We present two recoverable synchronization protocols, one blocking and another wait-free, which illustrate how to use software combining to achieve both low persistence and synchronization cost. Our experiments show that these protocols outperform by far state-of-the-art recoverable universal constructions and transactional memory systems. We built recoverable queues and stacks, based on these protocols, that exhibit much better performance than previous such implementations.

Cite as

Panagiota Fatourou, Nikolaos D. Kallimanis, and Eleftherios Kosmas. Brief Announcement: Persistent Software Combining. In 35th International Symposium on Distributed Computing (DISC 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 209, pp. 56:1-56:4, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)


Copy BibTex To Clipboard

@InProceedings{fatourou_et_al:LIPIcs.DISC.2021.56,
  author =	{Fatourou, Panagiota and Kallimanis, Nikolaos D. and Kosmas, Eleftherios},
  title =	{{Brief Announcement: Persistent Software Combining}},
  booktitle =	{35th International Symposium on Distributed Computing (DISC 2021)},
  pages =	{56:1--56:4},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-210-5},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{209},
  editor =	{Gilbert, Seth},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2021.56},
  URN =		{urn:nbn:de:0030-drops-148580},
  doi =		{10.4230/LIPIcs.DISC.2021.56},
  annote =	{Keywords: Persistent objects, recoverable algorithms, durability, synchronization protocols, software combining, universal constructions, wait-freedom, stacks, queues}
}
Document
An Efficient Universal Construction for Large Objects

Authors: Panagiota Fatourou, Nikolaos D. Kallimanis, and Eleni Kanellou

Published in: LIPIcs, Volume 153, 23rd International Conference on Principles of Distributed Systems (OPODIS 2019)


Abstract
This paper presents L-UC, a universal construction that efficiently implements dynamic objects of large state in a wait-free manner. The step complexity of L-UC is O(n+kw), where n is the number of processes, k is the interval contention (i.e., the maximum number of active processes during the execution interval of an operation), and w is the worst-case time complexity to perform an operation on the sequential implementation of the simulated object. L-UC efficiently implements objects whose size can change dynamically. It improves upon previous universal constructions either by efficiently handling objects whose state is large and can change dynamically, or by achieving better step complexity.

Cite as

Panagiota Fatourou, Nikolaos D. Kallimanis, and Eleni Kanellou. An Efficient Universal Construction for Large Objects. In 23rd International Conference on Principles of Distributed Systems (OPODIS 2019). Leibniz International Proceedings in Informatics (LIPIcs), Volume 153, pp. 18:1-18:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


Copy BibTex To Clipboard

@InProceedings{fatourou_et_al:LIPIcs.OPODIS.2019.18,
  author =	{Fatourou, Panagiota and Kallimanis, Nikolaos D. and Kanellou, Eleni},
  title =	{{An Efficient Universal Construction for Large Objects}},
  booktitle =	{23rd International Conference on Principles of Distributed Systems (OPODIS 2019)},
  pages =	{18:1--18:15},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-133-7},
  ISSN =	{1868-8969},
  year =	{2020},
  volume =	{153},
  editor =	{Felber, Pascal and Friedman, Roy and Gilbert, Seth and Miller, Avery},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2019.18},
  URN =		{urn:nbn:de:0030-drops-118049},
  doi =		{10.4230/LIPIcs.OPODIS.2019.18},
  annote =	{Keywords: universal construction, concurrent object, shared memory, simulation, wait-freedom, large object}
}
Document
Lock Oscillation: Boosting the Performance of Concurrent Data Structures

Authors: Panagiota Fatourou and Nikolaos D. Kallimanis

Published in: LIPIcs, Volume 95, 21st International Conference on Principles of Distributed Systems (OPODIS 2017)


Abstract
In combining-based synchronization, two main parameters that affect performance are the com- bining degree of the synchronization algorithm, i.e. the average number of requests that each com- biner serves, and the number of expensive synchronization primitives (like CAS, Swap, etc.) that it performs. The value of the first parameter must be high, whereas the second must be kept low. In this paper, we present Osci, a new combining technique that shows remarkable perform- ance when paired with cheap context switching. We experimentally show that Osci significantly outperforms all previous combining algorithms. Specifically, the throughput of Osci is higher than that of previously presented combining techniques by more than an order of magnitude. Notably, Osci’s throughput is much closer to the ideal than all previous algorithms, while keep- ing the average latency in serving each request low. We evaluated the performance of Osci in two different multiprocessor architectures, namely AMD and Intel. Based on Osci, we implement and experimentally evaluate implementations of concurrent queues and stacks. These implementations outperform by far all current state-of-the-art concur- rent queue and stack implementations. Although the current version of Osci has been evaluated in an environment supporting user-level threads, it would run correctly on any threading library, preemptive or not (including kernel threads).

Cite as

Panagiota Fatourou and Nikolaos D. Kallimanis. Lock Oscillation: Boosting the Performance of Concurrent Data Structures. In 21st International Conference on Principles of Distributed Systems (OPODIS 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 95, pp. 8:1-8:17, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2018)


Copy BibTex To Clipboard

@InProceedings{fatourou_et_al:LIPIcs.OPODIS.2017.8,
  author =	{Fatourou, Panagiota and Kallimanis, Nikolaos D.},
  title =	{{Lock Oscillation: Boosting the Performance of Concurrent Data Structures}},
  booktitle =	{21st International Conference on Principles of Distributed Systems (OPODIS 2017)},
  pages =	{8:1--8:17},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-061-3},
  ISSN =	{1868-8969},
  year =	{2018},
  volume =	{95},
  editor =	{Aspnes, James and Bessani, Alysson and Felber, Pascal and Leit\~{a}o, Jo\~{a}o},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2017.8},
  URN =		{urn:nbn:de:0030-drops-86282},
  doi =		{10.4230/LIPIcs.OPODIS.2017.8},
  annote =	{Keywords: Synchronization, concurrent data structures, combining}
}
Document
Wait-Free Concurrent Graph Objects with Dynamic Traversals

Authors: Nikolaos D. Kallimanis and Eleni Kanellou

Published in: LIPIcs, Volume 46, 19th International Conference on Principles of Distributed Systems (OPODIS 2015)


Abstract
Graphs are versatile data structures that allow the implementation of a variety of applications, such as computer-aided design and manufacturing, video gaming, or scientific simulations. However, although data structures such as queues, stacks, and trees have been widely studied and implemented in the concurrent context, multi-process applications that rely on graphs still largely use a sequential implementation where accesses are synchronized through the use of global locks or partitioning, thus imposing serious performance bottlenecks. In this paper we introduce an innovative concurrent graph model that provides addition and removal of any edge of the graph, as well as atomic traversals of a part (or the entirety) of the graph. We further present Dense, a concurrent graph implementation that aims at mitigating the two aforementioned implementation drawbacks. Dense achieves wait-freedom by relying on helping and provides the inbuilt capability of performing a partial snapshot on a dynamically determined subset of the graph.

Cite as

Nikolaos D. Kallimanis and Eleni Kanellou. Wait-Free Concurrent Graph Objects with Dynamic Traversals. In 19th International Conference on Principles of Distributed Systems (OPODIS 2015). Leibniz International Proceedings in Informatics (LIPIcs), Volume 46, pp. 27:1-27:17, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2016)


Copy BibTex To Clipboard

@InProceedings{kallimanis_et_al:LIPIcs.OPODIS.2015.27,
  author =	{Kallimanis, Nikolaos D. and Kanellou, Eleni},
  title =	{{Wait-Free Concurrent Graph Objects with Dynamic Traversals}},
  booktitle =	{19th International Conference on Principles of Distributed Systems (OPODIS 2015)},
  pages =	{27:1--27:17},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-939897-98-9},
  ISSN =	{1868-8969},
  year =	{2016},
  volume =	{46},
  editor =	{Anceaume, Emmanuelle and Cachin, Christian and Potop-Butucaru, Maria},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2015.27},
  URN =		{urn:nbn:de:0030-drops-66164},
  doi =		{10.4230/LIPIcs.OPODIS.2015.27},
  annote =	{Keywords: graph, shared memory, concurrent data structure, snapshot}
}
  • Refine by Type
  • 7 Document/PDF
  • 3 Document/HTML

  • Refine by Publication Year
  • 1 2026
  • 2 2025
  • 1 2021
  • 1 2020
  • 1 2018
  • Show More...

  • Refine by Author
  • 6 Fatourou, Panagiota
  • 4 Kallimanis, Nikolaos D.
  • 2 Kanellou, Eleni
  • 2 Kosmas, Eleftherios
  • 1 Attiya, Hagit
  • Show More...

  • Refine by Series/Journal
  • 7 LIPIcs

  • Refine by Classification
  • 4 Theory of computation → Concurrent algorithms
  • 3 Theory of computation → Data structures design and analysis
  • 1 Computing methodologies → Concurrent algorithms
  • 1 Computing methodologies → Concurrent computing methodologies
  • 1 Computing methodologies → Shared memory algorithms
  • Show More...

  • Refine by Keyword
  • 2 Synchronization
  • 2 combining
  • 2 shared memory
  • 2 wait-freedom
  • 1 Concurrent Data Structures
  • Show More...

Any Issues?
X

Feedback on the Current Page

CAPTCHA

Thanks for your feedback!

Feedback submitted to Dagstuhl Publishing

Could not send message

Please try again later or send an E-mail