From owner-freebsd-hackers Sun Oct 14 0:51: 9 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from freebsd.dk (fw-rl0.freebsd.dk [212.242.86.114]) by hub.freebsd.org (Postfix) with ESMTP id 563CC37B401; Sun, 14 Oct 2001 00:51:00 -0700 (PDT) Received: (from sos@localhost) by freebsd.dk (8.11.6/8.11.3) id f9E7oZi05487; Sun, 14 Oct 2001 09:50:35 +0200 (CEST) (envelope-from sos) From: Søren Schmidt Message-Id: <200110140750.f9E7oZi05487@freebsd.dk> Subject: Re: Severe I/O Problems In-Reply-To: To: mjacob@feral.com Date: Sun, 14 Oct 2001 09:50:34 +0200 (CEST) Cc: Jordan Hubbard , jrossiter@symantec.com, sos@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG Reply-To: sos@freebsd.dk X-Mailer: ELM [version 2.4ME+ PL94b (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG It seems Matthew Jacob wrote: > Just following up myself on this... with a drive on my PC164 Alpha, the > realtime difference between two different checkouts of cvs src is interesting: > > ------------- > > Script started on Sat Oct 13 10:07:07 2001 > farrago.feral.com > # this is with wc off > farrago.feral.com > /usr/bin/time cvs -q -d /home/ncvs co src > LOG > 2478.99 real 201.48 user 1046.87 sys > farrago.feral.com > exit > exit > > Script done on Sat Oct 13 10:55:36 2001 > Script started on Sat Oct 13 11:04:06 2001 > farrago.feral.com > # this is with wc on > farrago.feral.com > /usr/bin/time cvs -q -d /home/ncvs co src > LOG > 2866.82 real 199.92 user 988.24 sys > farrago.feral.com > exit > exit > > Script done on Sat Oct 13 11:57:51 2001 > ------------- > > All parameters were not totally lab controlled, but pretty close. I'd call it > significant enough that I'll leave WC off for this machine. Well I tried something semilar here, CVS tree on one disk, then newfs and cvs co src on another (both DTLA's on via686b if that matters) to keep things as equal as possible, singleuser mode of cause... -SU: softupdates -wc writecache enabled -tags tagged queing enabled res: 33.973u 19.425s 27:27.88 3.2% 583+7328k 47219+160828io 37pf+0w res-SU: 33.552u 16.235s 9:53.49 8.3% 586+7244k 47180+864io 6pf+0w res-wc: 32.959u 20.104s 3:38.23 24.3% 586+7317k 47232+160828io 37pf+0w res-wc-SU: 33.343u 16.909s 2:52.81 29.0% 585+7269k 47184+863io 6pf+0w res-wc-tags: 33.891u 29.705s 3:40.62 28.8% 587+7595k 47225+160548io 20pf+0w res-wc-tags-SU: 33.946u 20.759s 2:48.97 32.3% 578+7234k 47183+863io 5pf+0w That behaves more or less as I would expect... It is worth nothing that there is close to an order of magnitude in difference from the slowest to the fastest, and that WC is the single option that can make that difference on its own... -Søren To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message