Hi, Kris, On Sat, Feb 24, 2007 at 04:55:08PM -0500, Kris Kennaway wrote: > Now that the goals of the SMPng project are complete, for the past > year or more several of us have been working hard on profiling FreeBSD > in various multiprocessor workloads, and looking for performance > bottlenecks to be optimized. > > We have recently made significant progress on optimizing for MySQL > running on an 8-core amd64 system. The graph of results may be found > here: > > http://www.freebsd.org/~kris/scaling/scaling.png > > This shows the graph of MySQL transactions/second performed by a > multi-threaded client workload against a local MySQL database with > varying numbers of client threads, with identically configured FreeBSD > and Linux systems on the same machine.
I'm really glad to be looking at these results eventually. Thanks to all FreeBSD committers. > The test was run on FreeBSD 7.0, with the latest version of the ULE > 2.0 scheduler, the libthr threading library, and an uncommitted patch > from Jeff Roberson [1] that addresses poor scalability of file > descriptor locking (using a new sleepable mutex primitive); this patch > is responsible for almost all of the performance and scaling > improvements measured. It also includes some other patches (collected > in my kris-contention p4 branch) that have been shown to help > contention in MySQL workloads in the past (including a UNIX domain > socket locking pushdown patch from Robert Watson), but these were > shown to only give small individual contributions, with a cumulative > effect on the order of 5-10%. MySQL uses gettimeofday(2) very often. ISTR it has been stated that MySQL performances could make the most of a system-wide shared page where the current time would be updated regularly by the kernel; gettimeofday(2) could consequentely work without any context switch. Do the patches you're talking about include such a feature already ? Thank you. Best regards, -- Jeremie Le Hen < jeremie at le-hen dot org >< ttz at chchile dot org > _______________________________________________ freebsd-performance@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "[EMAIL PROTECTED]"
