From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 21 Sep 2004 02:33:16 -0700 From: William Lee Irwin III Subject: Re: [PATCH 2.6.9-rc2-mm1 0/2] mm: memory policy for page cache allocation Message-ID: <20040921093316.GG9106@holomorphy.com> References: <20040920190033.26965.64678.54625@tomahawk.engr.sgi.com> <20040920205509.GF4242@wotan.suse.de> <414F560E.7060207@sgi.com> <20040920223742.GA7899@wotan.suse.de> <414F8424.5080308@sgi.com> <20040921091353.GG8058@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040921091353.GG8058@wotan.suse.de> Sender: owner-linux-mm@kvack.org Return-Path: To: Andi Kleen Cc: Ray Bryant , Andrew Morton , Ray Bryant , linux-mm , Jesse Barnes , Dan Higgins , lse-tech , Brent Casavant , Nick Piggin , linux-kernel , Paul Jackson , Dave Hansen , stevel@mwwireless.net List-ID: On Mon, Sep 20, 2004 at 08:30:12PM -0500, Ray Bryant wrote: >> I'm sorry if this is confusing, personal terminology usually gets in the >> way. >> The idea is that just like for the page allocation policy (your current >> code), if you wanted, you would have a global, default page cache > On Tue, Sep 21, 2004 at 11:13:54AM +0200, Andi Kleen wrote: > Having both a per process page cache and a global page cache policy > would seem like overkill to me. > And having both doesn't make much sense anyways, because when the > system admin wants to change the global policy to free memory > on nodes he would still need to worry about conflicting per process policies > anyways. So as soon as you have process policy you cannot easily > change global anymore. Ray, would being able to change the default policy via kernel command- line options (and perhaps sysctl) suffice? It seems that a global default and some global state (e.g. per-cpu state) should largely capture what you're after. If not, could you clarify where it doesn't? Also, this switch statement stuff is getting a little hairy; maybe it's time to bring in mempolicy_ops. Or at least trudging through the switch () statements is turning into a moderate amount of work for me. -- wli -- 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: aart@kvack.org