On Mon, Apr 15, 2013 at 09:55:39AM -0400, Mike Snitzer wrote: > On Sat, Apr 13 2013 at 3:33pm -0400, > Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > > > On Sat, Apr 13 2013 at 12:09pm -0400, > > Joe Thornber <thornber@xxxxxxxxxx> wrote: > > > > > Hi Darrick, > > > > > > On Thu, Apr 11, 2013 at 12:22:39AM -0700, Darrick J. Wong wrote: > > > > Hi all, > > > > > > > > Lately I've been having some fun playing with bcache, dmcache, and enhanceio. > > > > > > I pushed some tweaks to the mq policy today to my thin-dev tree. They > > > show some improvements to these fio based tests. > > > > > > In addition I've written a blog post trying to explain what's going on in dm-cache: > > > http://device-mapper.org/blog/2013/04/13/benchmarking-dm-cache-with-fio/ > > > > Darrick, > > > > Joe has a few other dm-cache-target.c changes in his thin-dev branch > > that are required in order to realize the gains from his mq changes. I > > haven't yet isolated which changes are important but if I just use the > > 3.9-rc6's dm-cache-tagret.c with thin-dev's mq changes I cannot > > reproduce the improved performance Joe mentions in his blog post. > > I've now isolated the dm-cache-target.c commit in Joe's thin-dev that is > important to have in conjunction with the mq changes (from commit 7362f43a): > > commit f134e6382a534dd3622c3850e4824ae5929885d9 > Author: Joe Thornber <ejt@xxxxxxxxxx> > Date: Wed Mar 27 14:46:57 2013 +0000 > > [dm-cache] Change the default migration_threshold to something more suitable. > > diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c > index 8a4bcf3..f215307 100644 > --- a/drivers/md/dm-cache-target.c > +++ b/drivers/md/dm-cache-target.c > @@ -1948,7 +1948,7 @@ static sector_t calculate_discard_block_size(sector_t cache_block_size, > return discard_block_size; > } > > -#define DEFAULT_MIGRATION_THRESHOLD (2048 * 100) > +#define DEFAULT_MIGRATION_THRESHOLD 2048 > > static int cache_create(struct cache_args *ca, struct cache **result) > { You'll certainly need the new mq writeback stuff too. I don't know why you're intent on cherry picking. - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
