From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx106.postini.com [74.125.245.106]) by kanga.kvack.org (Postfix) with SMTP id 9E3FE6B0044 for ; Fri, 23 Mar 2012 04:05:27 -0400 (EDT) Received: by eaal1 with SMTP id l1so1081715eaa.14 for ; Fri, 23 Mar 2012 01:05:25 -0700 (PDT) Message-ID: <4F6C2E9B.9010200@gmail.com> Date: Fri, 23 Mar 2012 16:04:43 +0800 From: bill4carson MIME-Version: 1.0 Subject: Why memory.usage_in_bytes is always increasing after every mmap/dirty/unmap sequence Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "linux-mm@kvack.org" Hi, all I'm playing with memory cgroup, I'm a bit confused why memory.usage in bytes is steadily increasing at 4K page pace after every mmap/dirty/unmap sequence. On linux-3.6.34.10/linux-3.3.0-rc5 A simple test case does following: a) mmap 128k memory in private anonymous way b) dirty all 128k to demand physical page c) print memory.usage_in_bytes <-- increased at 4K after every loop d) unmap previous 128 memory e) goto a) to repeat And when the test case exit, memory.usage_in_bytes is not *ZERO*, but the previous increased value. I'm puzzled about what I saw, can anyone please give me some tips to understand this? Thanks in advance. -- Love each day! --bill -- 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