Re: False "lost ticks" on dual-Opteron system (=> timer twice as fast)

[Scott Robert Ladd <lkml@coyotegulch.com>]

Bernd Paysan <bernd.paysan@gmx.de> wrote:
>>I've recently set up a dual Opteron RAID server (AMD-8000-based Tyan
>>Thunder K8S Pro SCSI board, 2 246 Opterons, stepping 10). Kernel is a
>>modified 2.6.11.4-20a from SuSE 9.3 (SMP version, sure). The Opterons
>>are capable of changing the CPU frequency (between 1GHz and 2GHz).
>>
>>What I can't believe is that I'm the only one who has this problem.

Hendrik Visage wrote:
> I'll be delving deeper into this thread soon, but I'm seeing similar
> strangeness
> on a Athlon64 (rated:3G+ real:2009MHz clock), 2.6.11-r8 (gentoo), MSI
> K8N Neo Platinum.
> 
> ntp syncs time, then I start a couple of compiles, and I see ntp
> losing track of time, big jitter etc. (and the one time source is in
> on the local LAN syncing to the same remote servers). openntp I
> noticed it also.
> 
> What I have noticed in my dmesg output is that I see "lost timer ticks
> CPU Frequency change?" messages very early in the boot up.
> 
> I've seen this for about a week or three, and somehow I believe it
> wasn't a problem before 2.6.11.

I *don't* have any timer problems running 2.6.11-r8 (gentoo) on a dual
Opteron 250 system using a Tyan K8W 2885. Perhaps the problem is that
the two of you are running SCSI main drives, and I'm not?

..Scott