From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f176.google.com (mail-ob0-f176.google.com [209.85.214.176]) by kanga.kvack.org (Postfix) with ESMTP id 9C7F46B0038 for ; Fri, 30 Jan 2015 07:58:49 -0500 (EST) Received: by mail-ob0-f176.google.com with SMTP id va2so23697313obc.7 for ; Fri, 30 Jan 2015 04:58:49 -0800 (PST) Received: from mail-ob0-x236.google.com (mail-ob0-x236.google.com. [2607:f8b0:4003:c01::236]) by mx.google.com with ESMTPS id wo10si5262914oeb.19.2015.01.30.04.58.48 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 30 Jan 2015 04:58:49 -0800 (PST) Received: by mail-ob0-f182.google.com with SMTP id nt9so2468239obb.13 for ; Fri, 30 Jan 2015 04:58:48 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <54CAF9A4.1040606@samsung.com> References: <54CAF314.4070301@linaro.org> <54CAF9A4.1040606@samsung.com> Date: Fri, 30 Jan 2015 21:58:48 +0900 Message-ID: Subject: Re: CMA related memory questions From: Joonsoo Kim Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Heesub Shin Cc: Jun Nie , Arnd Bergmann , Marek Szyprowski , Shawn Guo , "mark.brown@linaro.org, wan.zhijun" , linux-arm-kernel@lists.infradead.org, Linux Memory Management List , sunae.seo@samsung.com, cmlaika.kim@samsung.com 2015-01-30 12:25 GMT+09:00 Heesub Shin : > > > On 01/30/2015 11:57 AM, Jun Nie wrote: >> >> On 2015=E5=B9=B401=E6=9C=8830=E6=97=A5 10:36, Jun Nie wrote: >>> >>> Hi Marek & Arnd, >>> >>> Did you ever know issue that free CMA memory is high, but system is >>> hungry for memory and page cache is very low? I am enabling CMA in >>> Android on my board with 512MB memory and see FreeMem in /proc/meminfo >>> increase a lot with CMA comparing the reservation solution on boot. But >>> I find system is not borrowing memory from CMA pool when running 3dmark >>> (high webkit workload at start). Because the FreeMem size is high, but >>> cache size decreasing significantly to several MB during benchmark run, >>> I suppose system is trying to reclaim memory from pagecache for new >>> allocation. My question is that what API that page cache and webkit >>> related functionality are using to allocate memory. Maybe page cache >>> require memory that is not movable/reclaimable memory, where we may hav= e >>> optimization to go thru dma_alloc_xxx to borrow CMA memory? I suppose >>> app level memory allocation shall be movable/reclaimable memory and can >>> borrow from CMA pool, but not sure whether the flag match the >>> movable/reclaimable memory and go thru the right path. Hello, Maybe, you experienced the problem what I tried to solve. CMA freepage allocation logic in mainline doesn't work well now since they are only allocated in fallback case. See below link for detailed explanation. https://lkml.org/lkml/2014/5/28/64 This problem can be solved by aggressive allocation approach in that link, = but, there are too many issues left in CMA. So, I'm trying to implement ZONE_CMA now. Prototyping is nearly finished so I will send it soon. Thanks. -- 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