Re: [GIT PULL] Ext3 latency fixes

[Jens Axboe <jens.axboe@oracle.com>]

On Sun, Apr 05 2009, Mark Lord wrote:
> Linus Torvalds wrote:
>>
>> Non-rotational media would tend to want the unplugging, but the block  
>> layer already does that (ie in __make_request() we already do:
>>
>>         if (unplug || blk_queue_nonrot(q))
>>                 __generic_unplug_device(q);
>>
>> so non-rotational devices get unplugged whether the request was a  
>> unplugging request or not).
> ..
>
> Mmm.. except that Jeff's SSD doesn't appear to identify itself
> as a non-rotating media.  I suppose there's a way to "quirk" that
> somewhere, though.

You can quirk it in userspace, just have it set the 'rotational' sysfs
file to 0 if it matches make/model/whatever.

-- 
Jens Axboe