I now have both servers booting with no apic and no acpi and keeping perfect time (with ntp running, without there was a minor drift of a couple of seconds over the course of a day). What is the down side to running this way? I noticed that certain interrupts are handled differently. One of my co-workers got the impression that this is part of a hardware abstraction layer that could lead to virtualization opportunities. Any idea what the purpose of moving interrupts (in my case for network cards and USB) to virtual interrupts is? sample below: [root at remus ~]# cat /proc/interrupts CPU0 0: 36662232 IO-APIC-edge timer 1: 9 IO-APIC-edge i8042 8: 26 IO-APIC-edge rtc 9: 0 IO-APIC-level acpi 12: 67 IO-APIC-edge i8042 14: 22214 IO-APIC-edge ide0 15: 329561 IO-APIC-edge ide1 177: 0 IO-APIC-level uhci_hcd 185: 218 IO-APIC-level uhci_hcd 193: 0 IO-APIC-level uhci_hcd 201: 2 IO-APIC-level ehci_hcd 217: 26007 IO-APIC-level eth0, eth1 225: 1030795 IO-APIC-level eth2 NMI: 0 LOC: 36663881 ERR: 0 MIS: 0 Regards, Chuck Chuck Mattern wrote: > First a grateful thank you to the individuals who posted responses and > an apology for not turning around faster. My day job is plagued with > a project that distinctly resembles the maiden voyage of HMS Titanic > and has been getting the best of me. > I'm trying the later fixes suggested in the bugzilla entry pointed to > by Zoran below (booting with " noapic noacpi apic=off acpi=off"). > Interestingly I had noted several of the issues covered in the > responses, different irq handling, ide disk involvement (the onset of > time problems seems to be hastened by high disk io). I'll report back > on the results. > > Regards, > Chuck > > Zoran Milojevic wrote: >> On 2/18/07, Chuck Mattern <camattern at acm.org> wrote: >>> -Systems will bog down critically after approximately 24 hours loosing >>> system time at an increasing rate, >> >> We have several IBM boxes (NetVista mostly) @work that would exhibit >> similar behavior - run normally at first, then after a few hours the >> system clock practically stops; I measured 2 minutes of wall-clock >> time for a "sleep 1" to return, and up to 20 seconds for "usleep 1"... >> Tried updating BIOS, kernel (4.3, 4.4, updates), some combinations of >> boot time parameters (as in: clock={pit|pmtmr|..}, noapic, acpi=off >> and the like), without improvement. We just gave up on those due to >> the lack of time. >> >> See also: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=203818 >> Solution from comment 18 may help (that comment was submitted after >> we've given up, not sure if it was tried). >> >> Cheers, >> Zoran > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos