Title
Eager Beats Lazy: Improving Store Management in Eager Hardware Transactional Memory
Abstract
Hardware transactional memory (HTM) designs are very sensitive to the manner in which speculative updates from transactions are handled in the system. This study highlights how the lack of effective techniques for store management results in a quick degradation in the performance of eager HTM systems with increasing contention and, thus, lends credence to the belief that eager designs do not perform as well as their lazy counterparts when conflicts abound. In this work, we present two simple ways to improve handling of speculative stores--a way to effectively manage lines that exhibit migratory sharing and a way to hide store latency, particularly for those stores that target contended cache lines owned by other concurrent transactions. These two mechanisms yield substantial improvements in execution time when running applications with high contention, allowing eager designs to exceed the performance of lazy ones. Interestingly, the benefits that accrue from these enhancements can be at par with those achieved using more complex system-wide HTM techniques. Coupled with the fact that eager designs are easier to integrate into cache coherent architectures than lazy ones, we claim that with judicious management of stores they represent a more compelling design alternative.
Year
DOI
Venue
2013
10.1109/TPDS.2012.315
IEEE Trans. Parallel Distrib. Syst.
Keywords
Field
DocType
cache coherent architecture,judicious management,eager beats lazy,cache line,eager design,speculative store,eager hardware transactional memory,high contention,simple way,eager htm system,improving store management,complex system-wide htm technique,lazy counterpart,concurrent computing,parallel processing,transactional memory,coherence,optimization,parallel programming,scalability,hardware,performance
Cache,Latency (engineering),Computer science,Eager evaluation,Real-time computing,Transactional memory,Execution time,Concurrent computing,Credence,Operating system,Scalability,Distributed computing
Journal
Volume
Issue
ISSN
24
11
1045-9219
Citations 
PageRank 
References 
4
0.39
15
Authors
5
Name
Order
Citations
PageRank
Rubén Titos-Gil17910.41
Anurag Negi2495.08
M. E. Acacio341941.45
Jose M. Garcia414513.30
Per Stenström53048234.09