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Concept

Optimistic concurrency control

Publications associées (28)

One-shot Garbage Collection for In-memory OLTP through Temporality-aware Version Storage

Anastasia Ailamaki, Periklis Chrysogelos, Angelos Christos Anadiotis, Syed Mohammad Aunn Raza

Most modern in-memory online transaction processing (OLTP) engines rely on multi-version concurrency control (MVCC) to provide data consistency guarantees in the presence of conflicting data accesses. MVCC improves concurrency by generating a new version o ...

ACM2023

Vision Transformer Adapters for Generalizable Multitask Learning

Sabine Süsstrunk, Mathieu Salzmann, Deblina Bhattacharjee

We introduce the first multitasking vision transformer adapters that learn generalizable task affinities which can be applied to novel tasks and domains. Integrated into an off-the-shelf vision transformer backbone, our adapters can simultaneously solve mu ...

Ieee Computer Soc2023

Improving K-means Clustering Using Speculation

Anastasia Ailamaki, Viktor Sanca, Eleni Zapridou, Stefan Igescu

K-means is one of the fundamental unsupervised data clustering and machine learning methods. It has been well studied over the years: parallelized, approximated, and optimized for different cases and applications. With increasingly higher parallelism leadi ...

2023

Concurrency control for database theorists

Christoph Koch, Bas Ketsman

The aim of this paper is to serve as a lightweight introduction to concurrency control for database theorists through a uniform presentation of the work on robustness against Multiversion Read Committed and Snapshot Isolation. ...

ASSOC COMPUTING MACHINERY2022

NrOS: Effective Replication and Sharing in an Operating System

Sanidhya Kashyap

Writing a correct operating system kernel is notoriously hard. Kernel code requires manual memory management and type-unsafe code and must efficiently handle complex, asynchronous events. In addition, increasing CPU core counts further complicate kernel de ...

USENIX ASSOC2021

Efficient Protocols for Enforcing Causal Consistency in Geo-Replicated Key-Value Data Stores

Kristina Spirovska

Modern large-scale data platforms manage colossal amount of data, generated by the ever-increasing number of concurrent users. Geo-replicated and sharded key-value data stores play a central role when building such platforms. As the strongest consistency m ...

EPFL2020

Locking Timestamps versus Locking Objects

Rachid Guerraoui, Tudor Alexandru David

We present multiversion timestamp locking (MVTL), a new genre of multiversion concurrency control algorithms for serializable transactions. The key idea behind MVTL is simple: lock individual timestamps instead of locking objects. After presenting a generi ...

ASSOC COMPUTING MACHINERY2018

Log-Free Concurrent Data Structures

Rachid Guerraoui, Aleksandar Dragojevic, Mihail Igor Zablotchi, Tudor Alexandru David

Non-volatile RAM (NVRAM) makes it possible for data structures to tolerate transient failures, assuming however that programmers have designed these structures such that their consistency is preserved upon recovery. Previous ap- proaches are typically tran ...

USENIX Association2018

Log-Free Concurrent Data Structures

Rachid Guerraoui, Mihail Igor Zablotchi, Aleksandar Dragojevic, Tudor Alexandru David

USENIX ASSOC2018

Program Analysis and Compilation Techniques for Speeding up Transactional Database Workloads

Mohammad Dashti Rahmat Abadi

There is a trend towards increased specialization of data management software for performance reasons. The improved performance not only leads to a more efficient usage of the underlying hardware and cuts the operation costs of the system, but also is a ga ...

EPFL2017

Optimistic Causal Consistency for Geo-Replicated Key-Value Stores

Willy Zwaenepoel, Diego Didona, Kristina Spirovska

In this paper we present a new approach to implementing causal consistency in geo-replicated data stores, which we call Optimistic Causal Consistency (OCC). The optimism in our approach lies in that updates from a remote data center are immediately made vi ...

Ieee Computer Soc2017

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

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

Techniques for Detection, Root Cause Diagnosis, and Classification of In-Production Concurrency Bugs

Baris Can Cengiz Kasikci

Concurrency bugs are at the heart of some of the worst bugs that plague software. Concurrency bugs slow down software development because it can take weeks or even months before developers can identify and fix them. In-production detection, root cause ...

EPFL2015

Consistency Models in Distributed Systems with Physical Clocks

Jiaqing Du

Most existing distributed systems use logical clocks to order events in the implementation of various consistency models. Although logical clocks are straightforward to implement and maintain, they may affect the scalability, availability, and latency of t ...

EPFL2014

Transactions Chasing Scalability and Instruction Locality on Multicores

Pinar Tözün

For several decades, online transaction processing (OLTP) has been one of the main server applications that drives innovations in the data management ecosystem, and in turn the database and computer architecture communities. Recent hardware trends oblige s ...

EPFL2014

Scaling up Mixed Workloads: a Battle of Data Freshness, Flexibility, and Scheduling

Anastasia Ailamaki, Iraklis Psaroudakis

The common "one size does not fit all" paradigm isolates transactional and analytical workloads into separate, specialized database systems. Operational data is periodically replicated to a data warehouse for analytics. Competitiveness of enterprises today ...

Springer International Publishing AG2015

Inferring Scalability from Program Pseudocode

Mihai Letia

Recent trends have led hardware manufacturers to place multiple processing cores on a single chip, making parallel programming the intended way of taking advantage of the increased processing power. However, bringing concurrency to average programmers is c ...

EPFL2014

From A to E: Analyzing TPC’s OLTP Benchmarks -- The obsolete, the ubiquitous, the unexplored

Anastasia Ailamaki, Ippokratis Pandis, Pinar Tözün, Dorde Jevdic, Ilknur Cansu Kaynak

Introduced in 2007, TPC-E is the most recently standardized OLTP benchmark by TPC. Even though TPC-E has already been around for six years, it has not gained the popularity of its predecessor TPC-C: all the published results for TPC-E use a single database ...

2013

Scaling up analytical queries with column-stores

Anastasia Ailamaki, Ioannis Alagiannis, Manoussos Gavriil Athanassoulis

As data analytics is used by an increasing number of applications, data analytics engines are required to execute workloads with increased concurrency, i.e., an increasing number of clients submitting queries. Data management systems designed for data anal ...

2013