Transactional memory (TM) is an attractive platform for parallel programs, and several software transactional memory (STM) designs have been presented. Here we explore several optimization opportunities to adapt to the running program and to adapt parameters that are optimized for the average case. Depending on the program the transactional load can vary per thread (e.g., client/server threads), or the program uses multiple phases of computation with different transactional loads. Therefore it is important that the STM adapts to the current situation, and that the adaptation process is short, efficient, and thread-local.
We present adaptSTM, a competitive, word-based STM library that is based on a global clock and an array of combined global versions (timestamps) and locks. To keep track of transactional data adaptSTM implements a multi-level buffer and uses read-set extension to achieve competitive performance.
The fine-grained adaptation system measures important runtime parameters like read- and write-locations, commit-, and abort-rate, and is able to adapt important parameters like write-set hash-size, hash function, and write strategy based on runtime statistics on a per-thread basis. Using the STAMP benchmarks, adaptSTM can be compared against other STM libraries.
- adaptSTM tech. report'10 with implementation details and comparison to other STM libraries.
- ISPASS'11 paper with a focus on performance evaluation.
- ISPASS'11 presentation for a quick overview.
If you have questions, problems, or bug reports please forward them to Mathias Payer firstname.lastname@example.org
- download and untar the current version of adaptSTM into a directory
- open the Makefile and select different optimizations
- maybe fine-tune the optimizations in adaptstm.h
- Run make
- Use lib/libadaptstm.a in your projects by including include/adaptstm-external.h
- Have fun