From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 0C3536B003D for ; Thu, 7 May 2009 12:42:53 -0400 (EDT) Received: from localhost (smtp.ultrahosting.com [127.0.0.1]) by smtp.ultrahosting.com (Postfix) with ESMTP id 91AD082C4BD for ; Thu, 7 May 2009 12:55:35 -0400 (EDT) Received: from smtp.ultrahosting.com ([74.213.175.254]) by localhost (smtp.ultrahosting.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zVJu095HAHYU for ; Thu, 7 May 2009 12:55:35 -0400 (EDT) Received: from qirst.com (unknown [74.213.171.31]) by smtp.ultrahosting.com (Postfix) with ESMTP id ACD7382C4D4 for ; Thu, 7 May 2009 12:55:28 -0400 (EDT) Date: Thu, 7 May 2009 12:32:40 -0400 (EDT) From: Christoph Lameter Subject: Re: [PATCH -mm] vmscan: make mapped executable pages the first class citizen In-Reply-To: <1241712000.18617.7.camel@lts-notebook> Message-ID: References: <20090430072057.GA4663@eskimo.com> <20090430174536.d0f438dd.akpm@linux-foundation.org> <20090430205936.0f8b29fc@riellaptop.surriel.com> <20090430181340.6f07421d.akpm@linux-foundation.org> <20090430215034.4748e615@riellaptop.surriel.com> <20090430195439.e02edc26.akpm@linux-foundation.org> <49FB01C1.6050204@redhat.com> <20090501123541.7983a8ae.akpm@linux-foundation.org> <20090503031539.GC5702@localhost> <1241432635.7620.4732.camel@twins> <20090507121101.GB20934@localhost> <1241705702.11251.156.camel@twins> <1241712000.18617.7.camel@lts-notebook> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Lee Schermerhorn Cc: Peter Zijlstra , Wu Fengguang , Andrew Morton , Rik van Riel , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , Elladan , Nick Piggin , Johannes Weiner , KOSAKI Motohiro List-ID: On Thu, 7 May 2009, Lee Schermerhorn wrote: > > Another possibility may be to put the exec pages on the mlock list > > and scan the list if under extreme duress? > > Actually, you don't need to go thru the overhead of mucking with the > PG_mlocked flag which incurs the rmap walk on unlock, etc. If one sets > the the AS_UNEVICTABLE flag, the pages will be shuffled off the the > unevictable LRU iff we ever try to reclaim them. And, we do have the > function to scan the unevictable lru to "rescue" pages in a given > mapping should we want to bring them back under extreme load. We'd need > to remove the AS_UNEVICTABLE flag, first. This is how > SHM_LOCK/SHM_UNLOCK works. We need some way to control this. If there would be a way to simply switch off eviction of exec pages (via /proc/sys/vm/never_reclaim_exec_pages or so) I'd use it. -- 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