From owner-freebsd-stable Fri Oct 27 8:18:35 2000 Delivered-To: freebsd-stable@freebsd.org Received: from mmap.nyct.net (mmap.nyct.net [216.44.109.243]) by hub.freebsd.org (Postfix) with ESMTP id 23C2C37B479 for ; Fri, 27 Oct 2000 08:18:31 -0700 (PDT) Received: by mmap.nyct.net (Postfix, from userid 1000) id 99038F9AC; Fri, 27 Oct 2000 11:17:23 -0400 (EDT) Date: Fri, 27 Oct 2000 11:17:23 -0400 From: Michael Bacarella To: freebsd-stable@FreeBSD.ORG Subject: vm_page_remove() problem.. Message-ID: <20001027111723.A9057@mmap.nyct.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii User-Agent: Mutt/1.0.1i Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG This keeps happening to one of our multiprocessor servers. About twice a day. panic: vm_page_remove(): page not found in hash mp_lock = 01000001; cpuid = 1; lapic.id = 01000000 boot() called on cpu#1 syncing disks... 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 giving up on 67 buffers Uptime: 21h28m53s Automatic reboot in 15 seconds - press a key on the console to abort Rebooting... cpu_reset called on cpu#1 cpu_reset: Stopping other CPUs cpu_reset: Restarting BSP cpu_reset_proxy: Grabbed mp lock for BSP cpu_reset_proxy: Stopped CPU 1 FreeBSD bsd10.nyct.net 4.1.1-STABLE FreeBSD 4.1.1-STABLE #0: Fri Oct 20 15:58:40 EDT 2000 myj@bsd6.nyct.net:/usr/obj/usr/src/sys/NYCT i386 We've tweaked some variables in response to this (maxusers?) but it doesn't seem to do the trick. It happens most when I do something memory intensive (like stopping and restarting apache, and all several-hundred children), but it really does happen quite randomly. My wild uneducated guess is that both processors are calling vm_page_remove() on a page and the one that doesn't happen first ends up panic'ing because it can't find the page anymore. We're in the process of trying it with a non-SMP kernel, but I figure I'd put this out early in any case as it's obviously a bug of some kind. If I really find myself at the end of a rope, I'm going to look to see if it's a hardware problem. Thanks -- Michael Bacarella ;finger address for public key GPG Key Fingerprint: B4E4 82F5 BCAC AB83 E6F7 B5AA 933E 2A75 79A4 A9C1 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message