XFS and nobarriers on Intel SSD

[Eric Sandeen]

On 9/3/15 8:33 AM, Eric Sandeen wrote:
> On 9/2/15 9:24 PM, Richard Bade wrote:

...

>> The reason I am asking about this is that we are seeing some
>> significant I/O delays on the disks causing a “SCSI Task Abort” from
>> the OS. This seems to be triggered by the drive receiving a
>> “Synchronize cache command”. My current thinking is that setting no
>> barriers will stop the drive receiving a sync command and therefore
>> stop the I/O delay associated with it.
> 
> Interesting, I thought that usually devices with battery-backed cache
> will just ignore synchronize cache commands.

Or more precisely, the device should advertise itself in such a way that
the commands wouldn't be sent, even if nobarrier wasn't specified...

-Eric

> But if not, then sure, maybe that's the issue.
> 
> -Eric