calcru went backwards on 7 stable

[Kris Kennaway]

Michael Powell wrote:
> Dimitar Vasilev wrote:
> 
>> Hi,
>> I'm having calcru went backwards issues on a machine with the following
>> config:
>>
>> MB: MSI K8D Master-F
>> 2xOpteron 242 2.2Ghz
>> BIOS - от 2005-та
>> 7-stable
>> areca 1120
>> 8 disks
>> HDD temperature 28-29 for 1st five,  38-39 for the last 3.
>>
>> bios is as of 2005 - ami bios or something like this.
>>
>> Initial time counter acpi-fast. changed it to i8245, but without success.
>> Problem is that I get 10-15 messages, after which machine freezes - and
>> it's not possible to log in via ssh.
>> then after some time it looses ping also and it has to be reset.
>>
>> smart says disks are ok.
>>
>> Could someone help on this?
>>
>> Thanks in advance!.
> 
> Only two things I can think of are to try the TSC timer as well, but sort 
> of doubt that will change anything. The other is if there is any CPU
> frequency speed reduction when idle (PowerNow!) settings in the BIOS try
> disabling that functionality. IIRC some of these had the ability for
> different cores/cpus to run at slightly different frequencies to reduce
> power consumption and this can really confuse the OS.

The "calcru went backwards" message can have two causes:

1) Your time counter really went backwards and is too broken to use.

2) Something caused clock interrupts to be delayed for extremely long 
periods of time.  This happens if you break to DDB for example.  It can 
also happen if there are kernel bugs, maybe in a driver etc.  Try to 
enable additional debugging (WITNESS, INVARIANTS, etc; see the 
developers handbook) and see where it gets you.

Kris