Thursday, December 7, 2006
12:00 pm - 1:00 pm
University of Michigan
Rethink the Sync
I will be discussing external synchrony, a new model for local file I/O that provides the reliability and simplicity of synchronous I/O, yet also closely approximates the performance of asynchronous I/O. An external observer cannot distinguish the output of a computer with an externally synchronous file system from the output of a computer with a synchronous file system. No application modification is required to use an externally synchronous file system: in fact, application developers can program to the simpler synchronous I/O abstraction and still receive excellent performance. We have implemented an externally synchronous file system for Linux, called xsyncfs. Xsyncfs provides the same durability and ordering guarantees as those provided by a synchronously mounted ext3 file system. Yet, even for I/O-intensive benchmarks, xsyncfs performance is within 7% of ext3 mounted asynchronously. Compared to ext3 mounted synchronously, xsyncfs is up to two orders of magnitude faster.
Ed Nightingale is a 5th year graduate student at the University of Michigan. His research interests include operating systems, distributed systems and mobile computing.
Angela Miller, 8-6645, email@example.com
or visit http://www.pdl.cmu.edu/SDI/