From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id D6E758D0040 for ; Fri, 4 Feb 2011 13:17:35 -0500 (EST) MIME-Version: 1.0 Message-ID: <85990ed5-f5d4-4ab2-809c-d181c865e86d@default> Date: Fri, 4 Feb 2011 10:16:49 -0800 (PST) From: Dan Magenheimer Subject: [LSF/MM TOPIC] improving in-kernel transcendent memory Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: lsf-pc@linuxfoundation.org Cc: linux-mm@kvack.org The concepts of transcendent memory, including cleancache and frontswap, have now graduated beyond virtualization to have real value in a standalone kernel. See the proposed kztmem patch: http://lwn.net/Articles/423540/=20 For the page cache, this effectively extends the split LRU (active/inactive= ) page queues to now include a new "queue" containing compressed clean page cache pages. For swap (as with ramzswap/zram), compressed in-memory swap pages may negatively impact memory pressure in some workloads and a method needs to be contrived to move these pages to a physical swap disk. Some things to discuss: 1) What is the appropriate page count balance between the active queue, the inactive queue, and cleancache-compressed pages? 2) What triggers can be used for rebalancing? 3) Is there a better "source" for cleancache than pages reclaimed from the inactive queue? 4) Under what conditions should frontswap-compressed pages be "repatriated" to normal kernel memory (and possibly to disk)? I also hope to also be able to describe and possibly demo a brand new in-ke= rnel (non-virtualization) user of transcendent memory (including both cleancache and frontswap) that I think attendees in ALL tracks will find intriguing, b= ut I'm not ready to talk about until closer to LSF/MM workshop. (Hopefully, this will make a good lightning talk.) Thanks, Dan Magenheimer -- 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