Publications de Vasileios Trigonakis

Thread-Placement Learning

Rachid Guerraoui, Vasileios Trigonakis, Karolos Antoniadis

In a non-uniform memory access machine, the placement of software threads to hardware cores can have a significant effect on the performance of concurrent applications. Detecting the best possible placement for each application is a necessity for thread sc ...

IEEE COMPUTER SOC2020

Lock-Unlock: Is That All? A Pragmatic Analysis of Locking in Software Systems

Rachid Guerraoui, Vasileios Trigonakis

A plethora of optimized mutex lock algorithms have been designed over the past 25 years to mitigate performance bottlenecks related to critical sections and locks. Unfortunately, there is currently no broad study of the behavior of these optimized lock alg ...

2019

TM 2 C: a software transactional memory for many-cores

Rachid Guerraoui, Vincent Gramoli, Vasileios Trigonakis

2018

Abstracting Multi-Core Topologies with MCTOP

Rachid Guerraoui, Vasileios Trigonakis, Georgios Chatzopoulos

Portability and efficiency are usually antagonists in multi-core computing. In order to develop efficient code, one needs to take into account the topology of the target multi-cores (e.g., for locality). This clearly hampers code portability. In this paper ...

ACM Press2017

FloDB: Unlocking Memory in Persistent Key-Value Stores

Rachid Guerraoui, Oana Maria Balmau, Mihail Igor Zablotchi, Vasileios Trigonakis

Log-structured merge (LSM) data stores enable to store and process large volumes of data while maintaining good performance. They mitigate the I/O bottleneck by absorbing updates in a memory layer and transferring them to the disk layer in sequential batch ...

2017

Sequential Proximity: Towards Provably Scalable Concurrent Search Algorithms

Rachid Guerraoui, Vasileios Trigonakis, Karolos Antoniadis, Julien Michel Stainer

Establishing the scalability of a concurrent algorithm a priori, before implementing and evaluating it on a concrete multi-core platform, seems difficult, if not impossible. In the context of search data structures however, according to all practical work ...

Springer International Publishing2017

Unlocking Energy

Rachid Guerraoui, Babak Falsafi, Javier Picorel Obando, Vasileios Trigonakis

Locks are a natural place for improving the energy efficiency of software systems. First, concurrent systems are mainstream and when their threads synchronize, they typically do it with locks. Second, locks are well-defined abstractions, hence changing the ...

Usenix Assoc2016

Towards Scalable Synchronization on Multi-Cores

Vasileios Trigonakis

The shift of commodity hardware from single- to multi-core processors in the early 2000s compelled software developers to take advantage of the available parallelism of multi-cores. Unfortunately, only few---so-called embarrassingly parallel---applications ...

EPFL2016

Optimistic Concurrency with OPTIK

Rachid Guerraoui, Vasileios Trigonakis

We introduce OPTIK, a new practical design pattern for designing and implementing fast and scalable concurrent data structures. OPTIK relies on the commonly-used technique of version numbers for detecting conflicting concurrent operations. We show how to i ...

ACM Press2016

Locking Made Easy

Rachid Guerraoui, Vasileios Trigonakis, Jelena Antic, Georgios Chatzopoulos

A priori, locking seems easy: To protect shared data from concurrent accesses, it is sufficient to lock before accessing the data and unlock after. Nevertheless, making locking efficient requires fine-tuning (a) the granularity of locks and (b) the locking ...

ACM Press2016

Asynchronized Concurrency: The Secret to Scaling Concurrent Search Data Structures

Rachid Guerraoui, Tudor Alexandru David, Vasileios Trigonakis

We introduce "asynchronized concurrency (ASCY),'' a paradigm consisting of four complementary programming patterns. ASCY calls for the design of concurrent search data structures (CSDSs) to resemble that of their sequential counterparts. We argue that ASCY ...

2015