From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id D31E56B0003 for ; Mon, 16 Apr 2018 07:41:47 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id d37so12675736wrd.21 for ; Mon, 16 Apr 2018 04:41:47 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 3si5566894edv.100.2018.04.16.04.41.46 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 16 Apr 2018 04:41:46 -0700 (PDT) Date: Mon, 16 Apr 2018 13:41:44 +0200 From: Michal Hocko Subject: Re: [PATCH 3/3] dcache: account external names as indirectly reclaimable memory Message-ID: <20180416114144.GK17484@dhcp22.suse.cz> References: <20180305133743.12746-1-guro@fb.com> <20180305133743.12746-5-guro@fb.com> <20180413133519.GA213834@rodete-laptop-imager.corp.google.com> <20180413135923.GT17484@dhcp22.suse.cz> <13f1f5b5-f3f8-956c-145a-4641fb996048@suse.cz> <20180413142821.GW17484@dhcp22.suse.cz> <20180413143716.GA5378@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180413143716.GA5378@cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Vlastimil Babka , Minchan Kim , Roman Gushchin , linux-mm@kvack.org, Andrew Morton , Alexander Viro , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com On Fri 13-04-18 10:37:16, Johannes Weiner wrote: > On Fri, Apr 13, 2018 at 04:28:21PM +0200, Michal Hocko wrote: > > On Fri 13-04-18 16:20:00, Vlastimil Babka wrote: > > > We would need kmalloc-reclaimable-X variants. It could be worth it, > > > especially if we find more similar usages. I suspect they would be more > > > useful than the existing dma-kmalloc-X :) > > > > I am still not sure why __GFP_RECLAIMABLE cannot be made work as > > expected and account slab pages as SLAB_RECLAIMABLE > > Can you outline how this would work without separate caches? I thought that the cache would only maintain two sets of slab pages depending on the allocation reuquests. I am pretty sure there will be other details to iron out and maybe it will turn out that such a large portion of the chache would need to duplicate the state that a completely new cache would be more reasonable. Is this worth exploring at least? I mean something like this should help with the fragmentation already AFAIU. Accounting would be just free on top. -- Michal Hocko SUSE Labs