Re: ahci(4) breaks on MSI X58 Pro-E

On 06.08.2011 12:27, Ed Schouten wrote:
> * Ed Schouten<ed_at_80386.nl>, 20110805 20:53:
>> The day before yesterday I upgraded a server of mine at Hetzner to
>> FreeBSD 9. It seems to use an MSI X58 Pro-E motherboard, having an ICH10
>> SATA-controller.
>>
>> It seems that under high load, I get timeouts on the SATA controller. It
>> seems disabling MSI has no effect. Unfortunately it's a sort-of
>> production system, so I can't do a lot of testing with it and I also
>> don't have any hands-on console access.
>
> False alarm. One of the hard disks of the server died, not long after I
> upgraded to 9. They replaced the disk and the system runs fine again.
>
> It should be noted that the ahci(4) driver made the system hang on
> timeouts, whereas the ata(4) driver already observed timeouts during
> startup and disabled the channel entirely. This allowed me to properly
> boot with a single disk.

ata(4) always had more strict command timeout settings. That could allow 
to recover faster, but caused problems in some cases. About a week ago 
I've committed few patches to improve error recovery in case when device 
completely stops responding. On my tests hung device dropped within 2-3 
minutes. If device is not completely dead, repeating recovery may take 
more time, but obviously this case has no right solution. If you have 
some disk redundancy, you may try to reduce number of command retries to 
make system recover faster.

-- 
Alexander Motin