Re: Bug: timer going backward on a dual core

[Vladimir Lazarenko <vlad@lazarenko.net>]

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>>>>>We have a dual-core AMD64 with the new kernel 2.6.14 and the
>>>>>timer goes backward...
>>>>>
>>>>>
>>>>>CONFIGURATION:
>>>>>
>>>>>Kernel: 2.6.14
>>>>>Distribution: Gentoo Linux 2005.0
>>>>>Processor: Athlon 64 x2 4200+ (dual core)
>>>>>Motherboard: Abit KN8
>>>>>Memory: 1GB PC3200
>>>>>
>>>>>
>>>>>PROBLEM:
>>>>>
>>>>>gettimeofday goes backward and returns values that are not monotonic,
>>>>>giving values that are smaller than values returned before.
>>>>>
>>>>>The system has been tested with timer as PIT, PIT/TSC and PM and the
>>>>>problem occurs with all the configurations.
>>>>>
>>>>>Here is the config file that we used for the PM configuration.
>>>>>
>>>>>Any suggestion ?
>>>>
>>>>Booting w/ idle=poll tends to work around this issue. You might check
>>>>with your motherboard vendor for an updated BIOS that supports HPET or
>>>>the ACPI PM timer.
>>>
>>>We already updated the BIOS with the latest version.
>>>
>>>Also the booting command idle=poll doesn't work.
>>
>>Hmm. Not sure then. Is this a new regression on the same hardware?
> Yes, we tried with idle=poll and the problem occurred again.

Very strange, idle=poll fixed it for us just fine.

Configuration we use is as follows:
Athlon 64 X2 3800+
Debian 32-bit
Tyan K8E
4G PC3200

Vladimir

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