neCODEC: nearline data compression for scientific applications

摘要

Advances on multicore technologies lead to processors with tens and soon hundreds of cores in a single socket, resulting in an ever growing gap between computing power and available memory and I/O bandwidths for data handling. It would be beneficial if some of the computing power can be transformed into gains of I/O efficiency, thereby reducing this speed disparity between computing and I/O. In this paper, we design and implement a NEarline data COmpression and DECompression (neCODEC) scheme for data-intensive parallel applications. Several salient techniques are introduced in neCODEC, including asynchronous compression threads, elastic file representation, distributed metadata handling, and balanced subfile distribution. Our performance evaluation indicates that neCODEC can improve the performance of a variety of data-intensive microbenchmarks and scientific applications. Particularly, neCODEC is capable of increasing the effective bandwidth of S3D, a combustion simulation code, by more than 5 times.