From owner-freebsd-current@FreeBSD.ORG Mon Apr 16 11:46:31 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E7BEF16A401 for ; Mon, 16 Apr 2007 11:46:31 +0000 (UTC) (envelope-from garyj@jennejohn.org) Received: from mail08a.verio.de (mail08a.verio.de [213.198.55.73]) by mx1.freebsd.org (Postfix) with SMTP id 3808C13C455 for ; Mon, 16 Apr 2007 11:46:31 +0000 (UTC) (envelope-from garyj@jennejohn.org) Received: from mx78.stngva01.us.mxservers.net (204.202.242.149) by mail08a.verio.de (RS ver 1.0.95vs) with SMTP id 3-0855413988 for ; Mon, 16 Apr 2007 13:46:29 +0200 (CEST) Received: from mmm808.verio.de [213.198.55.120] (EHLO mmm808.verio.de) by mx78.stngva01.us.mxservers.net (mxl_mta-1.3.8-10p4) with ESMTP id ab063264.11621.116.mx78.stngva01.us.mxservers.net; Mon, 16 Apr 2007 07:40:42 -0400 (EDT) Received: (qmail 53208 invoked from network); 16 Apr 2007 11:46:27 -0000 Received: from unknown (HELO peedub.jennejohn.org) (89.54.131.180) by with SMTP; 16 Apr 2007 11:46:27 -0000 Received: from jennejohn.org (localhost [127.0.0.1]) by peedub.jennejohn.org (8.14.1/8.14.1) with ESMTP id l3GBkQQi047570 for ; Mon, 16 Apr 2007 13:46:26 +0200 (CEST) (envelope-from garyj@jennejohn.org) Message-Id: <200704161146.l3GBkQQi047570@peedub.jennejohn.org> X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.0.4 To: freebsd-current@freebsd.org From: Gary Jennejohn Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 16 Apr 2007 13:46:26 +0200 Sender: garyj@jennejohn.org X-Spam: [F=0.5023916849; heur=0.500(0); stat=0.492; spamtraq-heur=0.510(2007022501)] X-MAIL-FROM: X-SOURCE-IP: [213.198.55.120] X-SF-Loop: 1 Subject: Re: Some comments on ZFS X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Apr 2007 11:46:32 -0000 I wrote: > With the old setup I saw: > a) ``make -j2 buildworld'' usually pegged the CPU at 97%. > [snip] > With the new setup: > a) ``make -j2 buildworld'' only reaches about 70% CPU load. Is ZFS stealing > so much CPU? > This turned out to be a problem with SCHED_ULE. I was seeing cpu0 80% idle almost all the time. After switching to SCHED_4BSD I see both CPUs used to within about 5% of each other. SCHED_4BSD tends to use cpu1 more than cpu0. SCED_ULE exhibited the same behavior, but more dramatically. -- Gary Jennejohn / garyjATjennejohnDOTorg gjATfreebsdDOTorg garyjATdenxDOTde