From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: Re: slab-nomerge (was Re: [git pull] device mapper changes for 4.3) Date: Wed, 2 Sep 2015 20:53:33 -0400 Message-ID: <20150903005332.GB27804@redhat.com> References: <20150902174815.199d51a480a01e9a754367e3@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20150902174815.199d51a480a01e9a754367e3@linux-foundation.org> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Linus Torvalds , Dave Chinner , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , "dm-devel@redhat.com" , Alasdair G Kergon , Joe Thornber , Mikulas Patocka , Vivek Goyal , Sami Tolvanen , Viresh Kumar , Heinz Mauelshagen , linux-mm List-Id: dm-devel.ids On Wed, Sep 02 2015 at 8:48pm -0400, Andrew Morton wrote: > On Wed, 2 Sep 2015 16:13:44 -0700 Linus Torvalds wrote: > > > On Wed, Sep 2, 2015 at 10:39 AM, Mike Snitzer wrote: > > > > > > - last but not least: add SLAB_NO_MERGE flag to mm/slab_common and > > > disable slab merging for all of DM's slabs (XFS will also use > > > SLAB_NO_MERGE once merged). > > > > So I'm not at all convinced this is the right thing to do. In fact, > > I'm pretty convinced it shouldn't be done this way. Since those > > commits were at the top of your tree, I just didn't pull them, but > > took the rest.. > > I don't have problems with the patch itself, really. It only affects > callers who use SLAB_NO_MERGE and those developers can make > their own decisions. > > It is a bit sad to de-optimise dm for all users for all time in order > to make life a bit easier for dm's developers, but maybe that's a > decent tradeoff. > > > What I do have a problem with is that afaict the patch appeared on > linux-mm for the first time just yesterday. Didn't cc slab developers, > it isn't in linux-next, didn't cc linux-kernel or linux-mm or slab/mm > developers on the pull request. Bad! Yeap, noted. Won't happen again. > I'd like the slab developers to have time to understand and review this > change, please. Partly so they have a chance to provide feedback for > the usual reasons, but also to help them understand the effect their > design choice had on client subystems. Sure, sorry to force the issue like I did. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org