From owner-freebsd-hackers Thu Nov 20 17:06:04 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id RAA27088 for hackers-outgoing; Thu, 20 Nov 1997 17:06:04 -0800 (PST) (envelope-from owner-freebsd-hackers) Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id RAA27079 for ; Thu, 20 Nov 1997 17:05:59 -0800 (PST) (envelope-from mrcpu@cdsnet.net) Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5]) by mail.cdsnet.net (8.8.6/8.8.6) with SMTP id RAA06865; Thu, 20 Nov 1997 17:05:51 -0800 (PST) Date: Thu, 20 Nov 1997 17:05:49 -0800 (PST) From: Jaye Mathisen To: "John S. Dyson" cc: hackers@FreeBSD.ORG Subject: Nope, didn't fix it.Re: Serious performance issue with 2.2.5-RELEASE In-Reply-To: <199711202155.QAA03288@dyson.iquest.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk OK, I handpatched the source, built a new kernel, and fired it up again. If anything, it's worse than before, hanging up within seconds of rebooting. I'm dropping back to the previous version for now, but this pretty well kills 2.2.5 for me for usability. I noticed that with this patch, I get very quick spikes in the la for the machine. Putting along around 3-3.5, then bam, spike to 15-20, then slowly comes back down. Yet top shows 52M Inact, 89M act, and only 195M swap used, out of a total of 744M. I notice now that a lot of processes seem to be in vmwait, when they didn't used to show it. Heck, I just had a la spike of 480. Machine kept running, but it was unable to serve files for 2-3 minutes. Help. On Thu, 20 Nov 1997, John S. Dyson wrote: > Jaye Mathisen said: > > > > > > I upgraded my web server to 2.2.5 from 2.2.2-stable, dated sometime in > > July. > > > > Big mistake. > > > > The only update to take place was the make buildworld, make installworld, > > no other configuration files were modified, nor any changes to startup > > scripts, etc. > > > > I now get these weird pauses where everything on the machine just freezes > > for 30-40 seconds, sometimes longer. NFS is compiled in, but not in use. > > > > The system was a web server, and was happily serving up several hundred > > domains. Now with the upgrade, I'll be lucky to keep them. Not good. > > > > It's a Super Micro P6, 384MB RAM, 2 SCSI disks off a bus-logic controller. > > > > Any ideas appreciated. I have built a new kernel from sources supped > > 11/7, but it doesn't seem to be any better. > > > Try this patch. The change in vfs_bio from 2.2.2 to 2.2.5 appears to be > incorrect, and subverts part of the functionality of what getnewbuf is > supposed to do. (Sorry, the patch might be reversed.) > > > Index: sys/kern/vfs_bio.c > =================================================================== > RCS file: /local/home/ncvs/src/sys/kern/vfs_bio.c,v > retrieving revision 1.104.2.7 > retrieving revision 1.104.2.3 > diff -C2 -r1.104.2.7 -r1.104.2.3 > *** vfs_bio.c 1997/09/01 23:23:08 1.104.2.7 > --- vfs_bio.c 1997/02/13 08:17:18 1.104.2.3 > *************** > *** 889,896 **** > /* wait for a free buffer of any kind */ > needsbuffer = 1; > ! do > ! tsleep(&needsbuffer, (PRIBIO + 1) | slpflag, "newbuf", > ! slptimeo); > ! while (needsbuffer); > return (0); > } > --- 872,877 ---- > /* wait for a free buffer of any kind */ > needsbuffer = 1; > ! tsleep(&needsbuffer, > ! (PRIBIO + 1) | slpflag, "newbuf", slptimeo); > return (0); > } > > > -- > John > dyson@freebsd.org > jdyson@nc.com >