Date: Sun, 7 May 2006 14:23:12 -0400 From: Kris Kennaway <kris@obsecurity.org> To: Robert Watson <rwatson@FreeBSD.org> Cc: Sven Petai <hadara@bsd.ee>, freebsd-performance@freebsd.org, performance@freebsd.org, current@freebsd.org Subject: Re: Fine-grained locking for POSIX local sockets (UNIX domain sockets) Message-ID: <20060507182312.GA185@xor.obsecurity.org> In-Reply-To: <20060507190844.K46997@fledge.watson.org> References: <20060506150622.C17611@fledge.watson.org> <200605071949.54978.hadara@bsd.ee> <20060507190844.K46997@fledge.watson.org>
next in thread | previous in thread | raw e-mail | index | archive | help
--bg08WKrSYDhXBjb5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, May 07, 2006 at 07:16:34PM +0100, Robert Watson wrote: >=20 > On Sun, 7 May 2006, Sven Petai wrote: >=20 > >I performed tests on a 4 * dualcore 2Ghz opteron system (so 8 cores in= =20 > >total). > > > >In general with 10 parallel smacker threads the performance seems to go = up=20 > >with your patch by ~44% and with 100 parallel threads it goes down ~25% >=20 > This is an interesting effect I need to explore. Kris reported much=20 > increased contention on locks within the process (between threads) when= =20 > running with my patch. It would be interesting to know what the effect o= n=20 > average query time is -- perhaps it has gone down and we're looking at=20 > increased scheduler related contention. >=20 > I noticed the results in the tests seem somewhat variable. I've noticed= =20 > that MySQL bennchmarking is heavily affected by test run time and order. = =20 > It's not atypical when running a series of identical tests to see a first= =20 > result half the end rate, a second result *better* than the end rate, and= =20 > then it balance out between the two. For example, I see the following on= a=20 Also, I see a slow but statistically significant deterioration in performance over time. Maybe mysql's memory is getting fragmented or something. Kris --bg08WKrSYDhXBjb5 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (FreeBSD) iD8DBQFEXjsQWry0BWjoQKURAtNGAJ0fM1JzVK9Rbj5c+7bunFj6oVGL/ACdFY+B gnscH3roaT5uePFlo4ek4vo= =af63 -----END PGP SIGNATURE----- --bg08WKrSYDhXBjb5--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20060507182312.GA185>