From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx180.postini.com [74.125.245.180]) by kanga.kvack.org (Postfix) with SMTP id E08026B00A8 for ; Tue, 21 May 2013 20:33:52 -0400 (EDT) Date: Tue, 21 May 2013 17:33:32 -0700 From: Andrew Morton Subject: Re: [PATCH v5 6/7] mm: Support address range reclaim Message-Id: <20130521173332.637942da.akpm@linux-foundation.org> In-Reply-To: <1368084089-24576-7-git-send-email-minchan@kernel.org> References: <1368084089-24576-1-git-send-email-minchan@kernel.org> <1368084089-24576-7-git-send-email-minchan@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Rik van Riel , Michael Kerrisk , Dave Hansen , Namhyung Kim , Minkyung Kim On Thu, 9 May 2013 16:21:28 +0900 Minchan Kim wrote: > This patch adds address range reclaim of a process. > The requirement is following as, > > Like webkit1, it uses a address space for handling multi tabs. > IOW, it uses *one* process model so all tabs shares address space > of the process. In such scenario, per-process reclaim is rather > coarse-grained so this patch supports more fine-grained reclaim > for being able to reclaim target address range of the process. > For reclaim target range, you should use following format. > > echo [addr] [size-byte] > /proc/pid/reclaim > > The addr should be page-aligned. > > So now reclaim konb's interface is following as. > > echo file > /proc/pid/reclaim > reclaim file-backed pages only > > echo anon > /proc/pid/reclaim > reclaim anonymous pages only > > echo all > /proc/pid/reclaim > reclaim all pages > > echo 0x100000 8K > /proc/pid/reclaim > reclaim pages in (0x100000 - 0x102000) This might be going a bit far. The application itself can be modified to use fadvise/madvise/whatever to release unused pages and that's a better interface. Athough it's a bit of a pipe-dream, I do think we should encourage userspace to go this path, rather than providing ways for hacky admin tools to go poking around in /proc/pid/maps and whacking apps externally. -- 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