Date: Tue, 09 Mar 2004 00:01:32 +0000 From: Mark Ovens <mark@ukug.uk.freebsd.org> To: freebsd-questions@freebsd.org Subject: Re: Wierd time changes Message-ID: <404D095C.6000301@ukug.uk.freebsd.org> In-Reply-To: <404CF162.4030202@ukug.uk.freebsd.org> References: <46848.206.169.45.183.1078783678.squirrel@mail.filmkern.com> <404CF162.4030202@ukug.uk.freebsd.org>
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Mark Ovens wrote: > Denis R. wrote: >> Hi Mark and list members, >> >> I am experiencing the same problem on my dual PII-450 SP700 Compaq Pro >> workstation. After poking around on Google, it is pointing to the FreeBSD >> and a i8254 programmable interupt timer. In my case the time is lagging >> behind 10 times! What does your: >> #time sleep 10 >> show? > > redshift# time sleep 10 > 0.000u 0.001s 0:10.00 0.0% 0+0k 0+0io 0pf+0w > redshift# > > The clock maintains the correct time whilst FreeBSD is running, it just > suddenly changes, at least somewhere "inside" FreeBSD, during shutdown > but doesn't screw the system clock until the next reboot, and even after > that it maintains consistent, but incorrect, time; i.e. it doesn't gain > or lose at a steady rate. > To follow up: Based on your comments Denis, I tried the kern.timecounter.hardware=i8254 workround - didn't work. I also spun a UP kernel - that didn't work either. Confirms that it is something specific to my machine (or the Asus A7M266-D m/b and BIOS). Where does FreeBSD store the corrupted time across reboots though and, more importantly, why? I don't know where to go from here. I do have an old IDE drive lying around so I guess I could put 4.9 on that and see if the problem exists there as well. Regards, Mark > Regards, > > Mark > >> It takes 25 seconds on my SMP workstation to execute a 10 second delay. I >> have modified the /etc/sysctl.conf and added: >> kern.timecounter.hardware=i8254 >> >> ntpd couldn't cope with this problem on my server. I have to run ntpdate >> every 10 minutes to set the time to an approximately accepted value :-(. >> >> There used to be a problem on older releases of FreeBSD (4.2 and up) >> related to a SMP kernel and clock. Someone posted a hack fix of the: >> usr/src/sys/i386/isa/clock.c file. But apparently it has been fixed in >> newer releases and does not get mentioned in 5.x. >> >> The most common fix I've heard from people is to recompile the kernel and >> exclude the SMP support. But if this is the case, I'd be switching to a >> mono CPU support of OpenBSD to run it. One of the reasons I like FreeBSD >> is its SMP support. >> >> People, any ideas? >> >> dmesg part: >> MPTable: <COMPAQ Workstation > >> Timecounter "i8254" frequency 1193182 Hz quality 0 >> uname -a: >> FreeBSD 5.2-RELEASE FreeBSD 5.2-RELEASE #0: Sun Jan 11 04:21:45 GMT 2004 >> root@wv1u.btc.adaptec.com:/usr/obj/usr/src/sys/GENERIC i386 >> >> Thanks and regards! >> Denis >> >> >>>>>>>>>>>>>>>>> >> I'm completely baffled by this one. When FreeBSD shuts down/reboots it >> changes the system clock. It *always* sets the hours to 20 and changes >> the minutes and seconds (but I haven't worked out a pattern for that), >> but the date stays the same (see /var/log/messages below) although I >> once saw it keep the time and date correct, but set the year back *four* >> years(!) but that was when the correct time was 22:mm:ss. >> >> >> _______________________________________________ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" >> >> . >> > > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" > > . >
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