From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Weiner Subject: Re: [patch 3/9] mm: memcontrol: retry reclaim for oom-disabled and __GFP_NOFAIL charges Date: Thu, 8 May 2014 14:28:48 -0400 Message-ID: <20140508182848.GP19914@cmpxchg.org> References: <1398889543-23671-1-git-send-email-hannes@cmpxchg.org> <1398889543-23671-4-git-send-email-hannes@cmpxchg.org> <20140507144339.GI9489@dhcp22.suse.cz> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=cmpxchg.org; s=zene; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date; bh=7V/P5U9vfO4ovPcxfuhkVp4M7p3D6ntengR6k92/PjA=; b=q4p+y6uTmoyJ3+y7m4Zb783l+Hf806b4L3ail/IG+Zf75sIUzeg51k6kNP9vihbLUKe8wZ4hvj5POHUI66NsQEbfXeydQzHtLA744H1M+X30CkJx5sPNUxKbRi+DeQ8Q5ytDGDXQO0/F0pshHqWSs+IVwbtFBEmmPkdp/xRf0Ns=; Content-Disposition: inline In-Reply-To: <20140507144339.GI9489@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michal Hocko Cc: linux-mm@kvack.org, Hugh Dickins , Tejun Heo , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org On Wed, May 07, 2014 at 04:43:39PM +0200, Michal Hocko wrote: > On Wed 30-04-14 16:25:37, Johannes Weiner wrote: > > There is no reason why oom-disabled and __GFP_NOFAIL charges should > > try to reclaim only once when every other charge tries several times > > before giving up. Make them all retry the same number of times. > > I guess the idea whas that oom disabled (THP) allocation can fallback to > a smaller allocation. I would suspect this would increase latency for > THP page faults. If it does, we should probably teach THP to use __GFP_NORETRY. On that note, __GFP_NORETRY is currently useless for memcg because it has !__GFP_WAIT semantics... I'll include a fix for that in v2. -- 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