Re: libata timeouts when stressing a Samsung HDD

[Tejun Heo <tj@kernel.org>]

Mark Lord wrote:
> Mark Lord wrote:
>> Chuck Ebbert wrote:
>>
>>> How do I change the timeout?
>> ..
>>
>> Heh.. actually, I'm not entirely sure myself.
>> This stuff bounces between the block, scsi, and ata layers,
>> and I think it's set before it gets to libata.
> ..
> 
> Mmm.. I think it is the SD_TIMEOUT value, defined in drivers/scsi/sd.h
> which currently uses (30 * HZ) as the timeout for most things,
> including for cache flushes.
> 
> Try changing it to (180 * HZ) just for fun.

Yeap, SD_TIMEOUT should be it.  But I've never personally seen disk
flushing taking as long as 30 seconds.  Does it really happen?  It's
not like the drive would be doing random seeking.  One full stroke
across the platter should be it.  Even with the rotational delay,
going over 30 seconds doesn't seem very likely.

Thanks.

-- 
tejun