On Thu 2009-08-27 12:54:05, Jeff Garzik wrote:
> On 08/27/2009 09:10 AM, Ric Wheeler wrote:
>> One thing that does need fixing for some MD configurations is to stress
>> again that we need to make sure that barrier operations are properly
>> supported or users will need to disable the write cache on devices with
>> volatile write caches.
>
> Agreed; chime in on Christoph's linux-vfs thread if people have input.
>
> I quickly glanced at MD and DM. Currently, upstream, we see a lot of
>
> if (unlikely(bio_barrier(bio))) {
> bio_endio(bio, -EOPNOTSUPP);
> return 0;
> }
>
> in DM and MD make_request functions.
>
> Only md/raid1 supports barriers at present, it seems. None of the other
> MD drivers support barriers.
Not even md/raid0? Ouch :-(.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
