Circuit design of a dual-versioning L1 data cache
Integration, the VLSI Journal
Transactional prefetching: narrowing the window of contention in hardware transactional memory
Proceedings of the 21st international conference on Parallel architectures and compilation techniques
An integrated pseudo-associativity and relaxed-order approach to hardware transactional memory
ACM Transactions on Architecture and Code Optimization (TACO) - Special Issue on High-Performance Embedded Architectures and Compilers
SCIN-cache: Fast speculative versioning in multithreaded cores
ACM Transactions on Architecture and Code Optimization (TACO) - Special Issue on High-Performance Embedded Architectures and Compilers
| Hi-index | 0.00 |
Transactional Memory (TM) potentially simplifies parallel programming by providing atomicity and isolation for executed transactions. One of the key mechanisms to provide such properties is version management, which defines where and how transactional updates (new values) are stored. Version management can be implemented either eagerly or lazily. In Hardware Transactional Memory (HTM) implementations, eager version management puts new values in-place and old values are kept in a software log, while lazy version management stores new values in hardware buffers keeping old values in-place. Current HTM implementations, for both eager and lazy version management schemes, suffer from performance penalties due to the inability to handle two versions of the same logical data efficiently. In this paper, we introduce a reconfigurable L1 data cache architecture that has two execution modes: a 64KB general purpose mode and a 32KB TM mode which is able to manage two versions of the same logical data. The latter allows to handle old and new transactional values within the cache simultaneously when executing transactional workloads. We explain in detail the architectural design and internals of this Reconfigurable Data Cache (RDC), as well as the supported operations that allow to efficiently solve existing version management problems. We describe how the RDC can support both eager and lazy HTM systems, and we present two RDC-HTM designs. Our evaluation shows that the Eager-RDC-HTM and Lazy-RDC-HTM systems achieve 1.36x and 1.18x speedup, respectively, over state-of-the-art proposals. We also evaluate the area and energy effects of our proposal, and we find that RDC designs are 1.92x and 1.38x more energy-delay efficient compared to baseline HTM systems, with less than 0.3% area impact on modern processors.