From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262286AbVAUGi5 (ORCPT ); Fri, 21 Jan 2005 01:38:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262289AbVAUGi5 (ORCPT ); Fri, 21 Jan 2005 01:38:57 -0500 Received: from smtp106.mail.sc5.yahoo.com ([66.163.169.226]:39257 "HELO smtp106.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262285AbVAUGgZ (ORCPT ); Fri, 21 Jan 2005 01:36:25 -0500 Subject: Re: OOM fixes 2/5 From: Nick Piggin To: Andrew Morton Cc: Andrea Arcangeli , linux-kernel@vger.kernel.org, npiggin@novell.com In-Reply-To: <20050120222056.61b8b1c3.akpm@osdl.org> References: <20050121054840.GA12647@dualathlon.random> <20050121054916.GB12647@dualathlon.random> <20050120222056.61b8b1c3.akpm@osdl.org> Content-Type: text/plain Date: Fri, 21 Jan 2005 17:36:14 +1100 Message-Id: <1106289375.5171.7.camel@npiggin-nld.site> Mime-Version: 1.0 X-Mailer: Evolution 2.0.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2005-01-20 at 22:20 -0800, Andrew Morton wrote: > Andrea Arcangeli wrote: > > > > This is the forward port to 2.6 of the lowmem_reserved algorithm I > > invented in 2.4.1*, merged in 2.4.2x already and needed to fix workloads > > like google (especially without swap) on x86 with >1G of ram, but it's > > needed in all sort of workloads with lots of ram on x86, it's also > > needed on x86-64 for dma allocations. This brings 2.6 in sync with > > latest 2.4.2x. > > But this patch doesn't change anything at all in the page allocation path > apart from renaming lots of things, does it? > > AFAICT all it does is to change the default values in the protection map. > It does it via a simplification, which is nice, but I can't see how it > fixes anything. > > Confused. It does turn on lowmem protection by default. We never reached an agreement about doing this though, but Andrea has shown that it fixes trivial OOM cases. I think it should be turned on by default. I can't recall what your reservations were...?