From owner-freebsd-hackers Tue Jan 17 01:51:04 1995 Return-Path: hackers-owner Received: (from root@localhost) by freefall.cdrom.com (8.6.9/8.6.6) id BAA03999 for hackers-outgoing; Tue, 17 Jan 1995 01:51:04 -0800 Received: from titan.np.ac.sg (lsys@titan.np.ac.sg [153.20.24.72]) by freefall.cdrom.com (8.6.9/8.6.6) with SMTP id BAA03993 for ; Tue, 17 Jan 1995 01:50:58 -0800 Message-Id: <199501170950.BAA03993@freefall.cdrom.com> Subject: Re: Filesystem(?) preformance - 1.x and 2.0 To: hackers@FreeBSD.org Date: Tue, 17 Jan 1995 17:49:14 +0800 (SST) From: SysAdmin - Ng Pheng Siong Cc: lsys@np.ac.sg (SysAdmin) In-Reply-To: <199501111752.SAA01305@knobel.gun.de> from "Andreas Klemm" at Jan 11, 95 06:52:55 pm X-Mailer: ELM [version 2.4 PL21] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII Content-Length: 1698 Sender: hackers-owner@FreeBSD.org Precedence: bulk Andreas wrote: > My comment: "Check cables and connectors" ;-) Checked. Well, I've just discovered the '-l' option to 'time'. ;) Here are 2 consecutive runs of `time -l cat web2 > /dev/null' on the 1.x: /home/ngps/perf:$ time -l cat web2 >/dev/null 5.07 real 0.02 user 0.56 sys 160 maximum resident set size 34 average shared memory size 19 average unshared data size 128 average unshared stack size 204 page reclaims 0 page faults 0 swaps 306 block input operations 0 block output operations 0 messages sent 0 messages received 0 signals received 305 voluntary context switches 6 involuntary context switches /home/ngps/perf:$ time -l cat web2 >/dev/null 0.36 real 0.02 user 0.34 sys 152 maximum resident set size 34 average shared memory size 18 average unshared data size 128 average unshared stack size 48 page reclaims 0 page faults 0 swaps 0 block input operations 0 block output operations 0 messages sent 0 messages received 0 signals received 0 voluntary context switches 4 involuntary context switches The 2nd time around, no block input operation! On the 2.0 system, each of 2 consecutive runs causes block input ops. Can someone kindly provide a pointer as to what's happening, please? - PS -- Ng Pheng Siong * lsys@np.ac.sg * ngps@np.ac.sg Computer Centre, Ngee Ann Polytechnic, Singapore