From owner-freebsd-current@FreeBSD.ORG Mon Jun 1 08:36:50 2009 Return-Path: <owner-freebsd-current@FreeBSD.ORG> Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F1F7A1065675; Mon, 1 Jun 2009 08:36:50 +0000 (UTC) (envelope-from ohartman@mail.zedat.fu-berlin.de) Received: from outpost1.zedat.fu-berlin.de (outpost1.zedat.fu-berlin.de [130.133.4.66]) by mx1.freebsd.org (Postfix) with ESMTP id AB6F48FC21; Mon, 1 Jun 2009 08:36:50 +0000 (UTC) (envelope-from ohartman@mail.zedat.fu-berlin.de) Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost1.zedat.fu-berlin.de (Exim 4.69) with esmtp (envelope-from <ohartman@mail.zedat.fu-berlin.de>) id <1MB30j-0005JL-OC>; Mon, 01 Jun 2009 10:36:49 +0200 Received: from e178015162.adsl.alicedsl.de ([85.178.15.162] helo=thor.walstatt.dyndns.org) by inpost2.zedat.fu-berlin.de (Exim 4.69) with esmtpsa (envelope-from <ohartman@mail.zedat.fu-berlin.de>) id <1MB30j-00036k-LN>; Mon, 01 Jun 2009 10:36:49 +0200 Message-ID: <4A239323.1090707@mail.zedat.fu-berlin.de> Date: Mon, 01 Jun 2009 10:36:51 +0200 From: "O. Hartmann" <ohartman@mail.zedat.fu-berlin.de> User-Agent: Thunderbird 2.0.0.21 (X11/20090410) MIME-Version: 1.0 To: bf <bf2006a@yahoo.com> References: <15091.46749.qm@web39108.mail.mud.yahoo.com> In-Reply-To: <15091.46749.qm@web39108.mail.mud.yahoo.com> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Originating-IP: 85.178.15.162 X-Mailman-Approved-At: Mon, 01 Jun 2009 11:23:52 +0000 Cc: attilio@freebsd.org, freebsd-current@freebsd.org, Kip Macy <kmacy@freebsd.org> Subject: Re: signifanctly slowdown of FreeBSD 8.0-CURRENT/amd64 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current <freebsd-current.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, <mailto:freebsd-current-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current> List-Post: <mailto:freebsd-current@freebsd.org> List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, <mailto:freebsd-current-request@freebsd.org?subject=subscribe> X-List-Received-Date: Mon, 01 Jun 2009 08:36:51 -0000 bf wrote: > > --- On Sat, 5/30/09, Kip Macy <kmacy@freebsd.org> wrote: > > >> From: Kip Macy <kmacy@freebsd.org> >> Subject: Re: signifanctly slowdown of FreeBSD 8.0-CURRENT/amd64 >> To: "bf" <bf2006a@yahoo.com> >> Cc: freebsd-current@freebsd.org, attilio@freebsd.org, ohartman@mail.zedat.fu-berlin.de >> Date: Saturday, May 30, 2009, 11:55 PM >> >>> I'm running the r193133 amd64 with a custom kernel and >>> >> all debugging off >> >>> on an AMD Athlon64 3400+ single-core, and I haven't >>> >> noticed any significant >> >>> slowing, although I haven't been doing any systematic >>> >> benchmarking. >> >>> What would be the penalties of running an SMP -CURRENT >>> >> kernel on >> >>> single-core hardware with no hyperthreading? Can >>> >> anyone quantify the >> >>> typical added overhead? Or, counterintuitively, >>> >> would an SMP kernel >> >>> be better in some ways? >>> >>> >> He is trying to diagnose if the problem was introduced by >> enabling >> adaptive spinning on sx locks. They're only enabled on SMP >> kernels. >> >> Cheers, >> Kip >> >> > > So I inferred from his request to have Oliver (the original poster) > revert r193011. But it seems unlikely that this is solely or even mostly > responsible for the slowdown, as Oliver reported that it first began > to occur several weeks ago, and Attilio only committed r193011 on Friday > -- unless Oliver independently added ADAPTIVE_SX to his custom kernel > a few weeks ago. In any event, I'm still interested in any reports of > the relative performance of SMP vs. UP kernels on UP hardware that > anyone is able to share. > > Thanks, > b. > > > > Would the addition of ADAPTIVE_SX to a SMP kernel or kernel of any kind have perfomance issues, also performance gains?