Return to BSD News archive
Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.cs.su.oz.au!inferno.mpx.com.au!goliath.apana.org.au!news.syd.connect.com.au!news.mel.connect.com.au!yarrina.connect.com.au!news.mira.net.au!news.vbc.net!samba.rahul.net!rahul.net!a2i!news.PBI.net!decwrl!enews.sgi.com!sgigate.sgi.com!news.msfc.nasa.gov!newsfeed.internetmci.com!in2.uu.net!news.artisoft.com!not-for-mail From: mday@elbereth.org (Matt Day) Newsgroups: comp.unix.bsd.freebsd.misc,comp.os.linux.advocacy,comp.os.linux.misc Subject: Re: Linux or FreeBSD, which is more reliable? Date: 4 Apr 1996 23:51:25 -0700 Organization: none Lines: 20 Message-ID: <4k2ftd$f7c@coyote.Artisoft.COM> References: <4jt34a$1nm@news7.erols.com> <4jugkl$fun@cebaf4.cebaf.gov> NNTP-Posting-Host: coyote.artisoft.com Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:16937 comp.os.linux.advocacy:44292 comp.os.linux.misc:96840 In article <4jugkl$fun@cebaf4.cebaf.gov> doolitt@recycle.cebaf.gov (Larry Doolittle) writes: >Linux can only be expected to stay up 248 days, at which time the >100Hz jiffy counter will go negative. Solutions are: > 1. Slow down the clock > 2. Run on an alpha (1024 Hz and 64-bit jiffies) > 3. Initialize jiffies to 214748000048 and debug what happens after an hour > 4. Add the line >/sbin/shutdown -r +705600 "running out of jiffies" > to your /etc/rc.d/rc.local (thanks, Werner) The jiffies counter (in both Linux 1.2.13 and 1.3.76) is an unsigned long, so it can't go negative. This means it should be good for at least 497 days, not 248. I took a cursory glance at the timer-list code (kernel/sched.c) in Linux 1.3.76 and it looks to me like it will indeed break when the jiffies counter rolls over. Could someone more familiar with the code verify this? It looks to me like the fix would be non-trivial. Matt Day <mday@elbereth.org>