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

From: Hendrik Visage
Date: Sat May 21 2005 - 14:44:22 EST


On 5/8/05, Bernd Paysan <bernd.paysan@xxxxxx> wrote:
> Hi,
>
> 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).

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.

> What I can't believe is that I'm the only one who has this problem.

I've seen this for about a week or three, and somehow I believe it
wasn't a problem before 2.6.11.

--
Hendrik Visage
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