From owner-freebsd-hackers@FreeBSD.ORG Sun Nov 25 20:16:03 2007 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3FD0916A473 for ; Sun, 25 Nov 2007 20:16:03 +0000 (UTC) (envelope-from muffaleta@gmail.com) Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.189]) by mx1.freebsd.org (Postfix) with ESMTP id C4B7F13C45B for ; Sun, 25 Nov 2007 20:16:02 +0000 (UTC) (envelope-from muffaleta@gmail.com) Received: by nf-out-0910.google.com with SMTP id b2so431850nfb for ; Sun, 25 Nov 2007 12:16:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=6Td1dWfcvZ2bT6W4Xud73gXC3pIQnjovHY8DwSFeoB4=; b=AvfjxsryztVDJp/gdGE7kIvFjzKuqaoDkhVGLUqOriy4o1x8hrWmjOgpgpDlzQe3N4L12yHMBpdflg68O/MLzgKk+WIJKyt/fc7mqIJ3UeekzTRTkYmk5QJOTQTIgwQNVsQ10FNOveXIZOtXbymd72Wwn1PBnzglA14FrWzBI88= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=RFXM78XhF3IPjuEddhfHxTYplWH9knKw3nUfGq+PespqvcAcitFJZBhlEkaAUCRhqlGJwuIBQCYBEY57RUGCOrHftenRhztKJmnbxVMkX32CfZlV5Wn4lppTb/ZdZC8QxZ4nH53kT29L4dGSBmN8pb0W+lOQPZNiiqTmS01q3RE= Received: by 10.82.183.19 with SMTP id g19mr5156023buf.1196021360412; Sun, 25 Nov 2007 12:09:20 -0800 (PST) Received: by 10.82.108.11 with HTTP; Sun, 25 Nov 2007 12:09:20 -0800 (PST) Message-ID: <7bc80d500711251209p3bd78bc0leb37d4cb85f677f3@mail.gmail.com> Date: Sun, 25 Nov 2007 12:09:20 -0800 From: "Christopher Chen" To: "Robert Watson" In-Reply-To: <7bc80d500711251205w1a74b649mc3bd374545c1012c@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <474830F9.90305@zirakzigil.org> <6eb82e0711240638g2cc1e54o1fb1321cafe8ff9f@mail.gmail.com> <1188.202.127.99.4.1195957922.squirrel@webmail.triplegate.net.id> <20071125110116.U63238@fledge.watson.org> <7bc80d500711251205w1a74b649mc3bd374545c1012c@mail.gmail.com> Cc: freebsd-hackers@freebsd.org Subject: Re: Before & After Under The Giant Lock X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 25 Nov 2007 20:16:03 -0000 On Nov 25, 2007 12:05 PM, Christopher Chen wrote: > On Nov 25, 2007 3:13 AM, Robert Watson wrote: > > At this point, Giant is gradually becoming a lock around the tty, newbus, usb, > > and msdosfs code, and we're largely at diminishing returns in terms of making > > improvements in parallelism through removing Giant. In FreeBSD 7, the focus > > was on improving parallelism rather than removing Giant, with improvements in > > locking primitives, the scheduler, and lock granularity. For example, most of > > the improvement in MySQL performance in FreeBSD 7 can be put down to a small > > number of changes: > > > > - Conversion to 1:1 threads from M:N threads. > > Dear Robert: > > I enjoyed reading your overview of changes from FreeBSD 6 to 7 with > regards to MP scalability, but I am a bit confused over this > point--Doesn't the user still have the choice between libthread, which > is M:N, and libthr, which is 1:1? > > At some point during the 6.x days, it was considered advantageous to > use libthr when running MySQL. Has the project decided to go with > libthread after all? > > Perhaps we're talking about entirely different things. My apologies. I re-read your statement and it makes sense now. I thought you were saying we were converting from 1:1 to M:N. Sorry for any confusion! -- Chris Chen "I want the kind of six pack you can't drink." -- Micah