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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!news.cs.su.oz.au!metro!metro!munnari.OZ.AU!news.ecn.uoknor.edu!news.ysu.edu!news.radio.cz!voskovec.radio.cz!news.radio.cz!CESspool!hammer.uoregon.edu!news.mathworks.com!fu-berlin.de!news.belwue.de!news.uni-ulm.de!rz.uni-karlsruhe.de!not-for-mail From: uk1o@rzstud2.rz.uni-karlsruhe.de (Felix Schroeter) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: Deciphering Kernel errors Date: 4 Feb 1997 17:48:18 +0100 Organization: University of Karlsruhe, Germany Lines: 32 Message-ID: <5d7p8i$1ib@rzstud2.rz.uni-karlsruhe.de> References: <32F00627.41C67EA6@silas.cc.monash.edu.au> NNTP-Posting-Host: rzstud2.rz.uni-karlsruhe.de Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:35119 Hello! In article <32F00627.41C67EA6@silas.cc.monash.edu.au>, Chooka <dhenshaw@silas.cc.monash.edu.au> wrote: >Recently whilst running a user PPP session I noticed the kernel reported >the following error >Jan 30 12:37:35 t-rex /kernel: sio1: 2 more silo overflows (total 2) >Can someone please tell me what this means ? Yes. The RS232 interface chipset can buffer only a few characters of input (1 on a 16450, 16 on 16550's). If the system (i.e. the kernel) doesn't fetch the characters from the hardware in time, characters are lost. The buffer in the RS232 chipset is called silo and the silo has overflowed in your case. The quoted syslog mesage is just a report that the kernel detected that characters have been lost this way twice (the kernel detects that via some error status bit[s] in the RS232 hardware). >How do I go about rectifying the problem ? If you don't have a 16550 or better, install at least a 16550 chip. >Are there any good kernel debugging sources available ? That's no kernel problem, but a hardware one. Do you have a slow CPU? Regards, Felix. [posted+emailed]