From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx202.postini.com [74.125.245.202]) by kanga.kvack.org (Postfix) with SMTP id 47A2B6B0104 for ; Tue, 8 May 2012 04:23:13 -0400 (EDT) Received: by dakp5 with SMTP id p5so9987134dak.14 for ; Tue, 08 May 2012 01:23:12 -0700 (PDT) Date: Tue, 8 May 2012 01:21:47 -0700 From: Anton Vorontsov Subject: Re: [PATCH 3/3] vmevent: Implement special low-memory attribute Message-ID: <20120508082147.GA22425@lizard> References: <20120504073810.GA25175@lizard> <20120507121527.GA19526@lizard> <4FA82056.2070706@gmail.com> <20120508065829.GA13357@lizard> <4FA8C86B.8010205@gmail.com> <20120508081305.GA20574@lizard> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20120508081305.GA20574@lizard> Sender: owner-linux-mm@kvack.org List-ID: To: KOSAKI Motohiro Cc: Pekka Enberg , Minchan Kim , Leonid Moiseichuk , John Stultz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org, patches@linaro.org, kernel-team@android.com On Tue, May 08, 2012 at 01:13:05AM -0700, Anton Vorontsov wrote: > On Tue, May 08, 2012 at 03:16:59AM -0400, KOSAKI Motohiro wrote: > [...] > > >So, feel free to call me an idiot, but please expand your points a > > >little bit or give a link to the discussion you're referring to? > > > > I don't think you are idiot. But I hope you test your patch before submitting. > > That just don't work especially on x86. Because of, all x86 box have multiple zone > > and summarized statistics (i.e. global_page_state() thing) don't work and can't > > prevent oom nor swapping. > > Now I think I understand you: we don't take into account that e.g. DMA > zone is not usable by the normal allocations, and so if we're basing our > calculations on summarized stats, it is indeed possible to get an OOM > in such a case. Oops. Looking into it more, I think I was wrong here: kernel will surely use pages from the DMA zone when we have no pages in normal zones. So, I don't see how we can get OOM in that case. Hm. -- Anton Vorontsov Email: cbouatmailru@gmail.com -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org