From owner-freebsd-questions Wed Feb 27 16:26:59 2002 Delivered-To: freebsd-questions@freebsd.org Received: from hermes.fm.intel.com (fmr01.intel.com [192.55.52.18]) by hub.freebsd.org (Postfix) with ESMTP id E14E537B41A; Wed, 27 Feb 2002 16:26:48 -0800 (PST) Received: from petasus.fm.intel.com (petasus.fm.intel.com [10.1.192.37]) by hermes.fm.intel.com (8.11.6/8.11.6/d: outer.mc,v 1.31 2002/02/19 21:16:00 root Exp $) with ESMTP id g1S0Pma01757; Thu, 28 Feb 2002 00:25:48 GMT Received: from fmsmsxvs040.fm.intel.com (fmsmsxv040-1.fm.intel.com [132.233.48.108]) by petasus.fm.intel.com (8.11.6/8.11.6/d: inner.mc,v 1.12 2002/02/09 00:15:52 root Exp $) with SMTP id g1S0PsM06058; Thu, 28 Feb 2002 00:25:54 GMT Received: from fmsmsx26.fm.intel.com ([132.233.42.26]) by fmsmsxvs040.fm.intel.com (NAVGW 2.5.1.16) with SMTP id M2002022716261425437 ; Wed, 27 Feb 2002 16:26:14 -0800 Received: by fmsmsx26.fm.intel.com with Internet Mail Service (5.5.2653.19) id <1Y30KF5Y>; Wed, 27 Feb 2002 16:26:37 -0800 Message-ID: From: "Frost, Stephen C" To: "'freebsd-questions@freebsd.org'" , "'freebsd-hackers@freebsd.org'" Subject: FreeBSD, SMP and Performance Speeds? Date: Wed, 27 Feb 2002 16:26:35 -0800 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG All - I have RTFM'd, with little luck. Can some enlightened soul impart knowledge upon me, thus letting me know why any kernels compiled with SMP enabled seem to be slowing the whole system down? Throughput goes down by 40%. Tasks take twice as long to run, etc, etc... I have multiple boxes (Dells, IBM's, Microns, Gateways...) running FreeBSd 4.5, all showing the same phenomenon. I initially mistook it for a NIC driver issue, but it appears to be system-wide. And is directly linked to SMP: two kernels, identical EXCEPT that one has SMP enabled, the other not. The enabled kernel that *should* be fully utilizing multi-procs is suddenly effectively running at half speed. Is this a config issue? Any helpful hints? Or is it better just to keep SMP disabled on a multi-proc box? Your adult supervision is appreciated. Thanks - -=C. Stephen Frost=- Intel Corp. ICG - Network Quality Labs Software Test Engineer 503.264.8300 All opinions are my own and other standard disclaimers... To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message