From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 17 Apr 2008 18:30:11 +0900 From: KOSAKI Motohiro Subject: Re: [PATCH 0/8][for -mm] mem_notify v6 In-Reply-To: References: <20080402154910.9588.KOSAKI.MOTOHIRO@jp.fujitsu.com> Message-Id: <20080417182121.A8CA.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Tom May Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: Hi Tom > Here's a test program that allocates memory and frees on notification. > It takes an argument which is the number of pages to use; use a > number considerably higher than the amount of memory in the system. > I'm running this on a system without swap. Each time it gets a > notification, it frees memory and writes out the /proc/meminfo > contents. What I see is that Cached gradually decreases, then Mapped > decreases, and eventually the kernel invokes the oom killer. It may > be necessary to tune some of the constants that control the allocation > and free rates and latency; these values work for my system. may be... I think you misunderstand madvise(MADV_DONTNEED). madvise(DONTNEED) indicate drop process page table. it mean become easily swap. when run on system without swap, madvise(DONTNEED) almost doesn't work as your expected. I am sorry for being not able to help you. ;) -- 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