From owner-freebsd-current Sun Apr 5 20:04:02 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id UAA06635 for freebsd-current-outgoing; Sun, 5 Apr 1998 20:04:02 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from dyson.iquest.net (dyson.iquest.net [198.70.144.127]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id UAA06607 for ; Sun, 5 Apr 1998 20:03:45 -0700 (PDT) (envelope-from toor@dyson.iquest.net) Received: (from root@localhost) by dyson.iquest.net (8.8.8/8.8.8) id WAA07645; Sun, 5 Apr 1998 22:03:36 -0500 (EST) (envelope-from toor) From: "John S. Dyson" Message-Id: <199804060303.WAA07645@dyson.iquest.net> Subject: Re: disk performance difference In-Reply-To: from Tamiji Homma at "Apr 5, 98 07:50:44 pm" To: thomma@slip.net (Tamiji Homma) Date: Sun, 5 Apr 1998 22:03:36 -0500 (EST) Cc: freebsd-current@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL38 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Hi, > > I am not a -current but SNAP CD user. I noticed something interesting, > that 19971006-SNAP disk performance is much greater than 19980222-SNAP > specially on my SCSI disk according to what Bonnie's says. In fact, > SCSI disk performance is very poor... > Try building a -current kernel, and I wonder if you see such a regression now. There have been several improvements (and fixes) lately. (It is fairly easy to build a -current kernel, running on a recent snapshot. Sometimes, you'll have to rebuild libkvm and ps, but shouldn't be a major problem, once you go through the learning curve.) > > 19980222-SNAP: 3315.51 real 2313.34 user 599.32 sys > 19971006-SNAP: 3370.48 real 2328.91 user 633.53 sys > > The 'make buildworld' is done under following conditions: > /usr/src on wd0 > /usr/obj on ccd0 (/dev/sd0c /dev/sd1c) > NOPROFILE, NOCLEAN, NOTCL, -pipe, async,noatime > > I don't see much difference (actually faster on newer SNAP, which is > good:) between two SNAPs when I do make buildworld. > > Can anybody elaborate why? > I don't have any details, but there have been numerous problems introduced in the name of improvements. It is likely that you are running a snap with the ioopt feature enabled, and that option was not well thought out before including in the tree. (I know, I implemented it.) John To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message