[dm-devel] [PATCH] dm thin: optimize away writing all zeroes to unprovisioned blocks

[Jens Axboe]

On 12/04/2014 08:33 AM, Mike Snitzer wrote:
>
> Here is a revised patch that is more like I'd expect to land upstream.
> Jens are you OK with us adding bio_is_zero_filled to block/bio.c?  If so
> should I split it out as a separate patch for you to pick up or just
> carry it as part of the patch that lands in linux-dm.git?

Yeah I'm fine with adding that helper. I do wonder what the performance 
impact is on this for dm. Have you tried a (worst case) test of writing 
blocks that are zero filled, but with the last byte not being a zero?

-- 
Jens Axboe