From owner-freebsd-questions Fri Sep 12 13:23:37 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id NAA05815 for questions-outgoing; Fri, 12 Sep 1997 13:23:37 -0700 (PDT) Received: from myplace.org (host-32-96-44-72.mia.bellsouth.net [32.96.44.72]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id NAA05800 for ; Fri, 12 Sep 1997 13:23:32 -0700 (PDT) Received: (from root@localhost) by myplace.org (8.7.5/8.7.3) id KAA00211 for questions@freebsd.org; Fri, 12 Sep 1997 10:16:31 -0400 (EDT) From: Keith Leonard Message-Id: <199709121416.KAA00211@myplace.org> Subject: refined silo overflow question To: questions@freebsd.org Date: Fri, 12 Sep 1997 10:16:30 -0400 (EDT) Reply-To: kleon@bellsouth.net (Keith Leonard) X-Mailer: ELM [version 2.4ME+ PL22 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Howdy, in going throught the mailing list search for the 'silo overflow' problem some experience I ran across this: Date: Thu, 4 May 1995 13:20:31 +1000 From: Bruce Evans To: hardware@FreeBSD.org, nc@ai.net, questions@FreeBSD.org Sender: questions-owner@FreeBSD.org Subject: Re: silo overflow!? w/ 16550s! >I have a system with 4 16550 capable serial ports. All run on their own >IRQ and I/O address. Two of the ports are internal modems [a 14.4 and a >28.8] and card has another 2 ports each connected to 28.8s. All ports [as >above] are 16550 UART'd. >When one connection is open full blast [a slip] there is no problem. The >minute I try to use kermit to dial out to a local system for giggles, or >even another modem on the same machine I get : >system /kernel: sio1: 1 more silo overflow (total of 10) for example. ************* THE IMPORTANT PART *************************** The 16550 fifo trigger level is set very agressively (to 14) to maximise efficiency. Dynamic adjustment of the trigger level (to 8, then 4, then 2, then 1) after silo overflows is #ifdef'ed off. A level of 8 would probably work for all 386/16 and faster systems with only 4 ports, provided they don't have bus-hogging DMA controller. You currently have to edit the sources to change the level. ************************************************************ Can someone tell me where this 'trigger level' is set and how to change it so that I might get rid of an annoying message to console. I need to recompile the kernel for the laptop anyway and it would sure be nice to clean up a few loose ends. (using ver. 2.1.5) Keith kleon@bellsouth.net ----------------------------------------------------------- Webmaster - http://www.rexart.com - Rex Artist Supplies ----------------------------------------------------------- Bombeck's Rule of Medicine: Never go to a doctor whose office plants have died.