From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id CCBD56B0005 for ; Wed, 27 Apr 2016 16:20:37 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id b203so104737110pfb.1 for ; Wed, 27 Apr 2016 13:20:37 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id bm3si11372122pad.35.2016.04.27.13.20.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Apr 2016 13:20:36 -0700 (PDT) Date: Wed, 27 Apr 2016 13:20:35 -0700 From: Andrew Morton Subject: Re: [PATCH v4 00/13] Support non-lru page migration Message-Id: <20160427132035.e96f99f3420c8fb0020b0fc4@linux-foundation.org> In-Reply-To: <1461743305-19970-1-git-send-email-minchan@kernel.org> References: <1461743305-19970-1-git-send-email-minchan@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Vlastimil Babka , dri-devel@lists.freedesktop.org, Hugh Dickins , John Einar Reitan , Jonathan Corbet , Joonsoo Kim , Konstantin Khlebnikov , Mel Gorman , Naoya Horiguchi , Rafael Aquini , Rik van Riel , Sergey Senozhatsky , virtualization@lists.linux-foundation.org, Gioh Kim , Chan Gyun Jeong , Sangseok Lee , Kyeongdon Kim , Chulmin Kim On Wed, 27 Apr 2016 16:48:13 +0900 Minchan Kim wrote: > Recently, I got many reports about perfermance degradation in embedded > system(Android mobile phone, webOS TV and so on) and easy fork fail. > > The problem was fragmentation caused by zram and GPU driver mainly. > With memory pressure, their pages were spread out all of pageblock and > it cannot be migrated with current compaction algorithm which supports > only LRU pages. In the end, compaction cannot work well so reclaimer > shrinks all of working set pages. It made system very slow and even to > fail to fork easily which requires order-[2 or 3] allocations. > > Other pain point is that they cannot use CMA memory space so when OOM > kill happens, I can see many free pages in CMA area, which is not > memory efficient. In our product which has big CMA memory, it reclaims > zones too exccessively to allocate GPU and zram page although there are > lots of free space in CMA so system becomes very slow easily. > > To solve these problem, this patch tries to add facility to migrate > non-lru pages via introducing new functions and page flags to help > migration. I'm seeing some rejects here against Mel's changes and our patch bandwidth is getting waaay way ahead of our review bandwidth. So I think I'll loadshed this patchset at this time, sorry. -- 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