From owner-freebsd-questions Fri Apr 12 14:57:39 1996 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id OAA11502 for questions-outgoing; Fri, 12 Apr 1996 14:57:39 -0700 (PDT) Received: from itsdsv1.enc.edu (itsdsv1.enc.edu [199.93.252.241]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id OAA11460 for ; Fri, 12 Apr 1996 14:57:30 -0700 (PDT) Received: from dingo.enc.edu (dingo.enc.edu [199.93.252.229]) by itsdsv1.enc.edu (8.6.12/8.6.9) with SMTP id RAA08365 for ; Fri, 12 Apr 1996 17:56:49 -0400 Date: Fri, 12 Apr 1996 18:00:00 -0400 (EDT) From: Charles Owens To: questions list FreeBSD Subject: unravelling page fault occurances Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk I understand the basics about the VM system and that a page fault occurs when the swapper tries to pull in a bit of memory that's been paged out and can't find it in the swap space. What other subtle stuff can come into play? I have a system (2.1-stable, running both NIS and quotas) that works well most of the time, but from time to time resets, particularily when I'm creating new uses (I've modified adduser to work with NIS and quotas). Most of the time I don't get any logging info, but once I've caught a glimpse of a page fault message on the console and today stuff actually showed up in the /var/log/messages file. Here's what I got while adding a user: Apr 12 10:21:07 itsdsv1 /kernel: Fatal trap 12: page fault while in kernel mode Apr 12 10:21:08 itsdsv1 /kernel: fault virtual address = 0x0 Apr 12 10:21:08 itsdsv1 /kernel: fault And, later, when I tried to create a few more users: Apr 12 10:40:16 itsdsv1 /kernel: Fatal trap 12: page fault while in kernel mode Apr 12 10:40:17 itsdsv1 /kernel: fault virtual address = 0x0 Apr 12 10:40:17 itsdsv1 /kernel: fault code = supervisor write, page not present Apr 12 10:40:17 itsdsv1 /kernel: instruction pointer = 0x8:0xf0180745 Apr 12 10:40:17 itsdsv1 /kernel: code segment = base 0x0, limit 0xfffff, type 0x1b Apr 12 10:40:17 itsdsv1 /kernel: = DPL 0, pres 1, def32 1, gran 1 Apr 12 10:40:17 itsdsv1 /kernel: processor eflags = interrupt enabled, resume, IOPL = 0 Apr 12 10:40:17 itsdsv1 /kernel: current process = 700 (popper) Apr 12 10:40:17 itsdsv1 /kernel: interrupt mask = Apr 12 10:40:17 itsdsv1 /kernel: panic: page fault Apr 12 10:40:17 itsdsv1 /kernel: Apr 12 10:40:17 itsdsv1 /kernel: syncing disks... What should I suspect? The quota system? My SCSI drives? Popper? FYI, it's a P100 ASUS P55TP4XE (512k PB-cache) system with an Acculogic SCSI controller (NCR 53c825). I have two SCSI drives: 1 gig SCSI-2: "DEC DSP3105S 392A" 4 gig SCSI-2 WIDE: "SEAGATE ST15230W 0298" Any direction would be most appreciated. If more info about the system or system logs would help, just holler... thanks, --- ------------------------------------------------------------------------- Charles Owens Email: owensc@enc.edu "I read somewhere to learn is to Information Technology Services remember... and I've learned that Eastern Nazarene College we've all forgot..." - King's X -------------------------------------------------------------------------