AWOL: An AdaptiveWrite Optimizations Layer

usenix08_button.jpgAlexandros Batsakis, Randal Burns, Arkady Kanevsky, James Lentini, and Thomas Talpey.

This paper presents I/O performance improvements from adaptively allocating memory between write buffering and read caching and opportunistically writing dirty pages.

Operating system memory managers fail to consider the population of read versus write pages in the buffer pool or outstanding I/O requests when writing dirty pages to disk or network file systems. This leads to bursty I/O patterns, which stall processes reading data and reduce the efficiency of storage. We address these limitations by adaptively allocating memory between write buffering and read caching and by writing dirty pages to disk opportunistically before the operating system submits them for write-back. We implement and evaluate our methods within the Linux® system and show performance gains of more than 30% for mixed read/write workloads.

In Proceedings of the USENIX Conference on File and Storage Technologies 2008 (FAST ’08)

Resources

  • A copy of the paper is attached to this posting.

awol_fast08.pdf