From owner-freebsd-questions@FreeBSD.ORG Sat Dec 10 11:49:00 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0A5FE16A41F for ; Sat, 10 Dec 2005 11:49:00 +0000 (GMT) (envelope-from maxsec@gmail.com) Received: from zproxy.gmail.com (zproxy.gmail.com [64.233.162.199]) by mx1.FreeBSD.org (Postfix) with ESMTP id C0F9F43D5A for ; Sat, 10 Dec 2005 11:48:58 +0000 (GMT) (envelope-from maxsec@gmail.com) Received: by zproxy.gmail.com with SMTP id l8so1081925nzf for ; Sat, 10 Dec 2005 03:48:58 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:subject:cc:in-reply-to:mime-version:content-type:references; b=VFDFE11LGbeXyJl5oZx7QaqCk47Ezwb2II6rweSWGtQiNe+kOYLzuxzwiOX2mrLZrVnnUsCeO5szgiZMSmCTwFkzHKIuLohGuz+GFEXLWp5jP2+V92MAgSOMP87gKYxcBnttDohw/qtm+jvEq44Xrk+3W1znmlXG1e2NXbxUU3o= Received: by 10.64.253.17 with SMTP id a17mr4688090qbi; Sat, 10 Dec 2005 03:48:57 -0800 (PST) Received: by 10.64.213.10 with HTTP; Sat, 10 Dec 2005 03:48:57 -0800 (PST) Message-ID: <72cf361e0512100348s6c1e86cfv23153da1a9f4078c@mail.gmail.com> Date: Sat, 10 Dec 2005 11:48:57 +0000 From: Martin Hepworth Cc: freebsd-questions@freebsd.org In-Reply-To: <20051209012022.GE80362@wantadilla.lemis.com> MIME-Version: 1.0 References: <4B3EE484EEA4F344BBB62F8316489986554680@corpsrv.RedMoon.local> <20051209012022.GE80362@wantadilla.lemis.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Re: BSD vs Linux Threads X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 10 Dec 2005 11:49:00 -0000 On 12/9/05, Greg 'groggy' Lehey wrote: > > [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 th= e > >> 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. Well yes they are, normally due to poor or zero tuning of the queries etc....tuning RDBMS's is a science in itself andcan be quite specific tothe RDBMS in question 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. COuld well be that the mysql is optimised for lunix threading. Given it als= o run on Solaris etc I wonder it performs on the tradition commericial Unix variants? -- martin