From owner-freebsd-smp Fri Aug 1 09:10:44 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id JAA27027 for smp-outgoing; Fri, 1 Aug 1997 09:10:44 -0700 (PDT) Received: from mhub2.tc.umn.edu (0@mhub2.tc.umn.edu [128.101.131.52]) by hub.freebsd.org (8.8.5/8.8.5) with SMTP id JAA27020 for ; Fri, 1 Aug 1997 09:10:31 -0700 (PDT) Received: from gold.tc.umn.edu by mhub2.tc.umn.edu; Fri, 1 Aug 97 11:10:25 -0500 Received: from pub-13-b-148.dialup.umn.edu by gold.tc.umn.edu; Fri, 1 Aug 97 11:10:24 -0500 Date: Fri, 1 Aug 1997 11:07:38 -0500 (CDT) From: dave adkins To: Steve Passe cc: smp@FreeBSD.ORG Subject: Re: interrupt latency and silo overflows in SMP since 970729 In-Reply-To: <199708011557.JAA22422@Ilsa.StevesCafe.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-smp@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Fri, 1 Aug 1997, Steve Passe wrote: > Hi, > > > Have there been any changes since 970729 that could have increased > > interrupt latencies significantly in the SMP kernel? I'm used to a few > > silo overflows now and then but kernels after 970729 have seem to have > > increased their frequency by about a factor of ten. > > undef PEND_INTS in i386/include/smptests.h and let me know how it affects > things. > > -- > Steve Passe | powered by > smp@csn.net | Symmetric MultiProcessor FreeBSD > > > steve, It was the first thing I tried. Sorry I didn't mention it in the original post. I also disabled your profiling in mplock.s with no significant effect (as expected). To quantify the phenomenon, with 970729 kernel I see about 5 to 10 silo overflows per hour of connection. With 970731 kernel I see about 100 to 150 per hour and often drop ftp and cvsup with timeouts. The system boots on IDE but /usr and the rest are mounted on NCR SCSI so about the only IDE activity is in /bin, /etc, and /var. MotherBoard: tyan S1653D 2x200 Bios: award 4.01 Drives: ide, NCR scsi dave