ata timeouts under load

Miroslav Lachman 000.fbsd at
Mon Sep 14 15:57:45 UTC 2009

Mike Tancsa wrote:
> At 11:21 AM 9/14/2009, Miroslav Lachman wrote:
>> I have very similar problem with one disk in gmirror, but it is on 7.2 
>> not current.
>> Sep 14 04:48:29 jimi kernel: ad6: timeout waiting to issue command
>> Sep 14 04:48:29 jimi kernel: ad6: error issuing FLUSHCACHE command
>> Sep 14 04:48:29 jimi kernel: ad6: TIMEOUT - READ_DMA48 retrying (1 
>> retry left) LBA=447001516
>> Sep 14 04:48:29 jimi kernel: ad6: FAILURE - READ_DMA48 
>> status=51<READY,DSC,ERROR> error=4<ABORTED> LBA=447001516
> Are you sure this is not just a bad cable ? I have had similar symptoms 
> which was a result of a bad cable.  If possible, swap the cable between 
> the 2 disks and see if it follows the cable.

I know it can be caused by bad cables, but everytime I see it with bad 
cables, it was without "timeout waiting to issue command" and "error 
issuing FLUSHCACHE command". It was just "TIMEOUT - READ_DMA48..." and 
similar messages (on different machines in the past).
The messages above is from server running for a year without problems, 
but disk load is higher and filesystem space is more used then before.

Miroslav Lachman

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