From owner-freebsd-questions@FreeBSD.ORG Fri Jan 21 13:47:16 2005 Return-Path: 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 0CD6116A4CE for ; Fri, 21 Jan 2005 13:47:16 +0000 (GMT) Received: from rogers.com (CPE00095bf5ff21-CM000f9f578d7a.cpe.net.cable.rogers.com [70.24.145.136]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8E33B43D55 for ; Fri, 21 Jan 2005 13:47:15 +0000 (GMT) (envelope-from gbell72@gardnerbell.ca) Received: from gardnerbell.ca (localhost [127.0.0.1]) by rogers.com (8.13.1/8.13.1) with ESMTP id j0LDipPH077710; Fri, 21 Jan 2005 08:44:51 -0500 (EST) (envelope-from gbell72@gardnerbell.ca) Received: (from gbell72@localhost) by gardnerbell.ca (8.13.1/8.13.1/Submit) id j0LDik4h077709; Fri, 21 Jan 2005 08:44:46 -0500 (EST) (envelope-from gbell72) Date: Fri, 21 Jan 2005 08:44:46 -0500 From: Gardner Bell To: stheg olloydson Message-ID: <20050121134446.GB77496@gardnerbell.ca> Mail-Followup-To: stheg olloydson , freebsd-questions@freebsd.org References: <20050121054859.40902.qmail@web53908.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050121054859.40902.qmail@web53908.mail.yahoo.com> User-Agent: Mutt/1.4.2.1i cc: freebsd-questions@freebsd.org Subject: Re: Thread Scheduling X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Jan 2005 13:47:16 -0000 On Thu, Jan 20, 2005 at 09:48:59PM -0800 stheg olloydson wrote: > it was said: > > > > >My question is, will I notice any performance improvement by using the > >new scheduler opposed to the 4.4BSD scheduler on an SMP system and can > >the new scheduler be utilized on a single processor system? The > >intended use of the SMP system is for MySQL databases only. > > > > Hello, > > I asked about the new scheduler on the performance list. Below is > (posted on list) reply: > > >FWIW, one of the reasons that there hasn't been as much > >interest in SCHED_ULE lately is likely that several of the > >features previously only present in SCHED_ULE are now also > >present in SCHED_4BSD -- for example, making more effective > >uses of IPIs in reducing latency during inter-process > >communication across processors. While SCHED_ULE does contain > >a number of interesting things not present in SCHED_4BSD, the > >4BSD scheduler has hardly gone un-improved in that time. > >However, Jeff Robserson does seem to have picked up recently > >on both VFS SMP locking and ULE. The scheduler tracing and > >visualization tools he committed a couple of weeks ago are > >really quite neat tools. > > > >Robert N M Watson > > So we'll just have to wait until ULE is fully baked to see which > scheduler is best for a given application. For a more definitive > answer, you may want to ask directly on the performance list. > Thanks for your reply, I do have more questions regarding this so I'll ask away on the performance list. Gardner