From owner-freebsd-performance@FreeBSD.ORG Fri Oct 13 20:13:58 2006 Return-Path: X-Original-To: freebsd-performance@FreeBSD.ORG Delivered-To: freebsd-performance@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id EF49316A646 for ; Fri, 13 Oct 2006 20:13:58 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0DD1A43D90 for ; Fri, 13 Oct 2006 20:13:32 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 2787F1A3C19; Fri, 13 Oct 2006 13:13:25 -0700 (PDT) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 569C3514AF; Fri, 13 Oct 2006 16:13:21 -0400 (EDT) Date: Fri, 13 Oct 2006 16:13:21 -0400 From: Kris Kennaway To: Chuck Swiger Message-ID: <20061013201321.GA774@xor.obsecurity.org> References: <3731.71.56.92.181.1160009571.squirrel@www.stelesys.com> <200610120925.k9C9PmUK048690@lurza.secnetix.de> <20061012205342.GA62241@xor.obsecurity.org> <9500A2C9-07EB-4EEA-9477-9E6B4BFEB437@mac.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/9DWx/yDrRhgMJTb" Content-Disposition: inline In-Reply-To: <9500A2C9-07EB-4EEA-9477-9E6B4BFEB437@mac.com> User-Agent: Mutt/1.4.2.2i Cc: freebsd-performance@FreeBSD.ORG, Kris Kennaway , Eric Hodel Subject: Re: Help with improving mysql performance on 6.2PRE X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Oct 2006 20:13:59 -0000 --/9DWx/yDrRhgMJTb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Oct 13, 2006 at 11:49:04AM -0700, Chuck Swiger wrote: > On Oct 13, 2006, at 11:26 AM, Eric Hodel wrote: > >>>Or did that change recently? > >> > >>It's only on certain systems, apparently. > > > >Is there a list of systems where it is safe to use the TSC with =20 > >SMP? Or some script we can run? >=20 > The problem of the TSC clocks getting out of sync affects pretty much =20 > all AMD X2 dual-core CPUs, as well as the older 32-bit Althon MP =20 > CPUs; the Intel Xeon and Core Duo CPUs seem to do a lot better, =20 > although older Intel CPUs have also been reported to show problems =20 > with the TSC. >=20 > Disabling the fancy power-management capabilities (SpeedStep, =20 > PowerNow, Cool-n-quiet) to prevent the system from adjusting the CPU =20 > clock frequencies seems to reduce the extent of the problem. =20 > However, if you want your system clock to work reliably, using the =20 > ACPI-safe or i8254 timecounters is going to do much better than using =20 > the faster-but-unreliable TSC method. Beyond that, just see if it works ;-) Kris --/9DWx/yDrRhgMJTb Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQFFL/NgWry0BWjoQKURAlQ/AJ9GPXFiWr7wZDw+YLm2B3nV5XqWqwCfQkMS FEatqEPd4xFA++6nUFV6PWc= =0MD/ -----END PGP SIGNATURE----- --/9DWx/yDrRhgMJTb--