From owner-freebsd-hackers Tue Oct 28 03:28:46 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id DAA16042 for hackers-outgoing; Tue, 28 Oct 1997 03:28:46 -0800 (PST) (envelope-from owner-freebsd-hackers) Received: from server.local.sunyit.edu (A-T34.rh.sunyit.edu [150.156.210.241]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id DAA16037 for ; Tue, 28 Oct 1997 03:28:42 -0800 (PST) (envelope-from perlsta@cs.sunyit.edu) Received: from localhost (perlsta@localhost) by server.local.sunyit.edu (8.8.7/8.8.5) with SMTP id HAA02910; Tue, 28 Oct 1997 07:33:52 -0500 (EST) X-Authentication-Warning: server.local.sunyit.edu: perlsta owned process doing -bs Date: Tue, 28 Oct 1997 07:33:52 -0500 (EST) From: Alfred Perlstein X-Sender: perlsta@server.local.sunyit.edu To: Thomas David Rivers cc: freebsd-hackers@freefall.FreeBSD.org Subject: Re: sio silo overflows on a P75 @ 38400 baud? In-Reply-To: <199710281110.GAA06120@lakes.dignus.com> 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 if you've only seen three a day or so, it makes total sense that they might be occuring during the nightly/weekly/monthly scripts that seriously thrash your system. again it's easy to has 3 (or more) situtations, in your situation (not a lot of resources) where the system get's overloaded just for a few seconds or less causing the overflow... it's not more irritating, it's unavoidable. :) just think how many interupts there might be in second occuring on your serial port, just a little overactivity on the disk..... and wha-la. > > you are quite possbily over loading your system with a combination of > > writes and swapping (8megs of ram? ewwww) > > Hmm... good point. > > > > > if disk activity is constant it's quite possible to reach a load of 9.0+ > > i did while doing a buildworld and making my kernel -j8... it was at like > > 9.6+ at times... pretty cool as X kept freezing for several seconds at a > > time... > > But - the disk activity isn't constant; it's no where near that > (being a little twiddle about every 13 seconds). In fact, uptime > shows my load average as > 7:02AM up 8:52, 2 users, load averages: 0.00, 0.00, 0.00 > > So, I don't believe that's the culprit. > > In the span of this 8:52 hours, though, I've only seen 3 silo > overflows... So, the issue appears to be intermittent... (which > makes it more aggravating... :-) ) > > - Dave Rivers - > > > > > On Mon, 27 Oct 1997, Thomas David Rivers wrote: > > > > > > > > I was just wondering - should it be possible, at 38400 baud, > > > in multi-user mode, but nothing else really going on; to get > > > silo overflows on a P75 with 16550 (clone?) UARTs? > > > > > > I'm doing a SL/IP connection and sending the output of > > > dd'ing a tape back to the P75 system for un-tarring. The > > > sending system is a P200 (running FreeBSD 2.2-970510.) > > > > > > I'm getting these silo overflows with 2.2.5. > > > > > > I'm hoping someone can whip out some figures on the > > > interrupt latency to suggest that a P75 should be able > > > to deal with receiving 38400... > > > > > > This could, of course, be an artifact of some device > > > holding the bus too long. The P75 machine is a laptop > > > with a IDE drive (to which I'm writting) and 8 meg of memory; > > > again, running 2.2.5-RELEASE. > > > > > > - Thanks - > > > - Dave Rivers - > > > > > > > >