From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 21 May 2008 09:28:49 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC][PATCH 2/3] memcg:: seq_ops support for cgroup Message-Id: <20080521092849.c2f0b7e1.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <6599ad830805201146g5a2a8928l6a2f5adc51b15f15@mail.gmail.com> References: <20080520180552.601da567.kamezawa.hiroyu@jp.fujitsu.com> <20080520180841.f292beef.kamezawa.hiroyu@jp.fujitsu.com> <6599ad830805201146g5a2a8928l6a2f5adc51b15f15@mail.gmail.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: Paul Menage Cc: LKML , "linux-mm@kvack.org" , "balbir@linux.vnet.ibm.com" , "xemul@openvz.org" , "lizf@cn.fujitsu.com" , "yamamoto@valinux.co.jp" List-ID: On Tue, 20 May 2008 11:46:46 -0700 "Paul Menage" wrote: > On Tue, May 20, 2008 at 2:08 AM, KAMEZAWA Hiroyuki > wrote: > > Does anyone have a better idea ? > > As a way of printing plain text files, it seems fine. > > My concern is that it means that cgroups no longer has any idea about > the typing of the data being returned, which will make it harder to > integrate with a binary stats API. You'd end up having to have a > separate reporting method for the same data to use it. That's why the > "read_map" function specifically doesn't take a seq_file, but instead > takes a key/value callback abstraction, which currently maps into a > seq_file. For the binary stats API, we can use the same reporting > functions, and just map into the binary API output. > With current interface, my concern is hotplug. File-per-node method requires delete/add files at hotplug. A file for all nodes with _maps_ method cannot be used because maps file says == The key/value pairs (and their ordering) should not * change between reboots. == And (*read) method isn't useful ;) Can we add new stat file dynamically ? Thanks, -Kame -- 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