From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f170.google.com (mail-wi0-f170.google.com [209.85.212.170]) by kanga.kvack.org (Postfix) with ESMTP id A28746B0031 for ; Wed, 12 Feb 2014 05:39:30 -0500 (EST) Received: by mail-wi0-f170.google.com with SMTP id hi5so1495848wib.1 for ; Wed, 12 Feb 2014 02:39:29 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id e6si776125wik.35.2014.02.12.02.39.27 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 12 Feb 2014 02:39:28 -0800 (PST) Date: Wed, 12 Feb 2014 10:39:24 +0000 From: Mel Gorman Subject: Re: [PATCH 0/4] hugetlb: add hugepagesnid= command-line option Message-ID: <20140212103924.GO6732@suse.de> References: <1392053268-29239-1-git-send-email-lcapitulino@redhat.com> <20140211092514.GH6732@suse.de> <20140211152629.GA28210@amt.cnet> <20140211171035.GN6732@suse.de> <20140211201557.GA16281@amt.cnet> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20140211201557.GA16281@amt.cnet> Sender: owner-linux-mm@kvack.org List-ID: To: Marcelo Tosatti Cc: David Rientjes , Luiz Capitulino , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Andrea Arcangeli , Andi Kleen , Rik van Riel On Tue, Feb 11, 2014 at 06:15:57PM -0200, Marcelo Tosatti wrote: > On Tue, Feb 11, 2014 at 05:10:35PM +0000, Mel Gorman wrote: > > On Tue, Feb 11, 2014 at 01:26:29PM -0200, Marcelo Tosatti wrote: > > > > Or take a stab at allocating 1G pages at runtime. It would require > > > > finding properly aligned 1Gs worth of contiguous MAX_ORDER_NR_PAGES at > > > > runtime. I would expect it would only work very early in the lifetime of > > > > the system but if the user is willing to use kernel parameters to > > > > allocate them then it should not be an issue. > > > > > > Can be an improvement on top of the current patchset? Certain use-cases > > > require allocation guarantees (even if that requires kernel parameters). > > > > > > > Sure, they're not mutually exclusive. It would just avoid the need to > > create a new kernel parameter and use the existing interfaces. > > Yes, the problem is there is no guarantee is there? > There is no guarantee anyway and early in the lifetime of the system there is going to be very little difference in success rates. In case there is a misunderstanding here, I'm not looking to NAK a series that adds another kernel parameter. If it was me, I would have tried runtime allocation first to avoid adding a new interface but it's a personal preference. -- Mel Gorman SUSE Labs -- 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