From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH 3/7] CART - an advanced page replacement policy From: Peter Zijlstra In-Reply-To: <1128107781.14695.32.camel@twins> References: <20050929180845.910895444@twins> <20050929181622.780879649@twins> <20050930184404.GA16812@xeon.cnet> <1128107781.14695.32.camel@twins> Content-Type: text/plain Date: Fri, 30 Sep 2005 21:27:00 +0200 Message-Id: <1128108420.14695.37.camel@twins> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Marcelo Cc: Linux Kernel Mailing List , linux-mm@kvack.org List-ID: On Fri, 2005-09-30 at 21:16 +0200, Peter Zijlstra wrote: > On Fri, 2005-09-30 at 15:44 -0300, Marcelo wrote: > > Hi Peter, > > > > On Thu, Sep 29, 2005 at 08:08:48PM +0200, Peter Zijlstra wrote: > > > The flesh of the CART implementation. Again comments in the file should be > > > clear. > > > > Having per-zone "B1" target accounted at fault-time instead of a global target > > strikes me. > > > > The ARC algorithm adjusts the B1 target based on the fact that being-faulted-pages > > were removed from the same memory region where such pages will reside. > > > > The per-zone "B1" target as you implement it means that the B1 target accounting > > happens for the zone in which the page for the faulting data has been allocated, > > _not_ on the zone from which the data has been evicted. Seems quite unfair. > > > > So for example, if a page gets removed from the HighMem zone while in the > > B1 list, and the same data gets faulted in later on a page from the normal > > zone, Normal will have its "B1" target erroneously increased. > > > > A global inactive target scaled to the zone size would get rid of that problem. > > Good, good, I'll think this though, this probably means the other > targets: 'p' and 'r' would similarly benefit. I'm not thinking straigt, I should get back on my feet before I start touching that code. Thanks for the feedsback. Peter -- Peter Zijlstra -- 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