Improving the Message Channel of SAM Using Shared Memory

SAM is a parallel programming model in Haskell, suitable for manycore computing environments. It has been developed in two versions: SAMSoc adopting the socket communication and SAMSTM adopting the software transactional memory (STM). However, both versions of SAM do not always guarantee the best performance due to the overhead of synchronization. Therefore we have to select a specific version of SAMs to promote the performance depending on the number of cores available in the running environment. In this paper, we propose SAMShm, a new version of SAM, which shows good performance under any number of cores. SAMShm reduces the overhead of socket communication and garbage collection using the message channel based on shared memory. According to the performance test on the 72-core machine, the scalability of SAMShm is improved by 52% points over SAMSoc and 295% points over SAMSTM.