Date: Fri, 9 Dec 2005 11:50:22 +1030 From: Greg 'groggy' Lehey <grog@FreeBSD.org> To: Ted Mittelstaedt <tedm@toybox.placo.com> Cc: freebsd-questions@freebsd.org, Cody Holland <cholland@redmoonbroadband.com>, Kris Kennaway <kris@obsecurity.org> Subject: Re: BSD vs Linux Threads Message-ID: <20051209012022.GE80362@wantadilla.lemis.com> In-Reply-To: <LOBBIFDAGNMAMLGJJCKNOEOGFCAA.tedm@toybox.placo.com> References: <4B3EE484EEA4F344BBB62F8316489986554680@corpsrv.RedMoon.local> <LOBBIFDAGNMAMLGJJCKNOEOGFCAA.tedm@toybox.placo.com>
next in thread | previous in thread | raw e-mail | index | archive | help
--WBsA/oQW3eTA3LlM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline [resequenced] On Friday, 2 December 2005 at 22:27:51 -0800, Ted Mittelstaedt wrote: > On Thursday, December 01, 2005 12:36 PM, Cody Holland wrote: >> >> Well in the past it was stated that on a MySQL server installed using >> Linux threads was faster than using the native BSD threads. I'm in the >> process of building a new MySQL 5 server with FreeBSD 5.4 and was >> wanting to know if using the Linux threads was still faster. > > It probably is because mysql is optimized for the Linux threading > implementation. > Also keep in mind that freebsd filesystems are mounted async by default, > not sync by default like Linux, as a result FreeBSD always does worse > in these stupid bakeoffs you read about in the trade rags. Somebody else has pointed out that this was stated the wrong way round. But what we've seen so far is probably not related to the way the file systems are mounted. > You can install the linux threading package under FreeBSD's linux > emulation and try it that way. I don't think this is a useful option. Linuxthreads might be, though. > Keep in mind also that you are talking minute performance > differences on the newest multi-gigahertz systems. It would be nice if this were true. We've seen claims of performance differences in the order of 3:1. > Furthermore I will point out that unless your database is smaller > than physical memory of the server, then the argument between mysql > threading and non-threading is a completely moot issue since the > hits to the disk will be the bottleneck. Many database systems are CPU-bound. MySQL has identified that there are some serious issues with FreeBSD at the moment. As somebody with a foot in both camps, I'm keeping an open mind about where the problem is, but certainly the threading libraries are an issue. I wish I could make a specific recommendation. Greg -- When replying to this message, please take care not to mutilate the original text. For more information, see http://www.lemis.com/email.html See complete headers for address and phone numbers. --WBsA/oQW3eTA3LlM Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (FreeBSD) iD8DBQFDmNvWIubykFB6QiMRAuhUAKCe/CHK7wwLuWet/RggWp2WQ9sfDQCfYdS+ 7P6T6fOnVfffnbQ3aGKMWk0= =4R/T -----END PGP SIGNATURE----- --WBsA/oQW3eTA3LlM--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20051209012022.GE80362>