From owner-freebsd-hackers Tue Nov 24 14:25:32 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id OAA15046 for freebsd-hackers-outgoing; Tue, 24 Nov 1998 14:25:32 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from wrath.cs.utah.edu ([155.99.198.98]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id OAA15033 for ; Tue, 24 Nov 1998 14:25:30 -0800 (PST) (envelope-from danderse@cs.utah.edu) Received: from torrey.cs.utah.edu (torrey.cs.utah.edu [155.99.212.91]) by wrath.cs.utah.edu (8.8.8/8.8.8) with ESMTP id PAA23390; Tue, 24 Nov 1998 15:25:26 -0700 (MST) Received: (from danderse@localhost) by torrey.cs.utah.edu (8.9.1/8.9.1) id PAA00518; Tue, 24 Nov 1998 15:25:25 -0700 (MST) (envelope-from danderse@cs.utah.edu) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Tue, 24 Nov 1998 15:25:25 -0700 (MST) From: "David G. Andersen" To: hackers@FreeBSD.ORG CC: vanmaren@cs.utah.edu, sclawson@cs.utah.edu Subject: MFS hang when copying large file to it (vm problem?) X-Mailer: VM 6.43 under 20.4 "Emerald" XEmacs Lucid Message-ID: <13915.12507.346867.242762@torrey.cs.utah.edu> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Brief summary: System: 3.0-release (plus a few days of -current) Memory: 128M Swap: 512M on /dev/wd0s3b /tmp: 256M MFS backed to /dev/wd0s3b dd if=/dev/zero of=/tmp/zero bs=64k count={large enough to force swapping of the file being DD'd. 3000 does the trick nicely} will cause the system to hang. The symptoms are very similar to those reported in Feb. 1998 in: http://www.freebsd.org/cgi/getmsg.cgi?fetch=412721+415177+/usr/local/www/db/text/1998/freebsd-hackers/19980215.freebsd-hackers (Search for "VM AND messed" in -hackers to get the full thread) where Don Lewis stated: Do you think this could explaint the MFS related hangs I've been seeing in 2.1-stable? If I use MFS for /tmp, copy a large file into /tmp, delete the file, then copy it into /tmp again, the machine will hang. It responds to pings. It will also respond to ^T until I try to interrupt a process with ^C. The only way to unhang it is to use the reset button. It's fairly trivial to reproduce, but we're running SMP with our typical heavily networked environment. Has anyone encountered this, have a fix for it, or care to try to reproduce it on a less complicated machine, before I submit a PR and/or dig more deeply into it? Thanks in advance, -Dave -- work: danderse@cs.utah.edu me: angio@pobox.com University of Utah http://www.angio.net/ Department of Computer Science To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message