Re: Missed jiffies

From: H. Peter Anvin (hpa@zytor.com)
Date: Tue Feb 19 2002 - 15:23:46 EST


Pavel Machek wrote:

> Hi!
>
>
>>>lap tops), is the fact that TSC is NOT clocked at a fixed rate. It is
>>>affected by throttling (reduced in 12.5% increments) and by power
>>>management.
>>>
>>If the TSC is affected by HLT, throttling, or C2 power management, the
>>TSC is broken (as it is on Cyrix chips, for example.) The TSC usually
>>*is* affected by C3 power management, but the OS should be aware of
>>C3.
>>
>
> Add thinkpad 560X (pentium/MMX) and toshiba 4030cdt (celeron) to your
> blacklist, then. I believe that by your definition *many* sstems are
> broken.
> Pavel

It's sad but true. Unfortunately the TSC seems to be considered a
low-priority operation. It's for systems like the above you need the
"no-tsc" option.

        -hpa

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sat Feb 23 2002 - 21:00:21 EST