From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-we0-f182.google.com (mail-we0-f182.google.com [74.125.82.182]) by kanga.kvack.org (Postfix) with ESMTP id 8213C6B0037 for ; Mon, 2 Jun 2014 11:16:56 -0400 (EDT) Received: by mail-we0-f182.google.com with SMTP id t60so5214915wes.41 for ; Mon, 02 Jun 2014 08:16:55 -0700 (PDT) Received: from jenni2.inet.fi (mta-out1.inet.fi. [62.71.2.198]) by mx.google.com with ESMTP id r3si10739064wjw.87.2014.06.02.08.16.37 for ; Mon, 02 Jun 2014 08:16:37 -0700 (PDT) Date: Mon, 2 Jun 2014 18:16:29 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH] improve __GFP_COLD/__GFP_ZERO interaction Message-ID: <20140602151629.GA8160@node.dhcp.inet.fi> References: <538CAA520200007800016E87@mail.emea.novell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <538CAA520200007800016E87@mail.emea.novell.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jan Beulich Cc: linux-mm@kvack.org, David Vrabel , mingo@elte.hu, tglx@linutronix.de, Boris Ostrovsky , Konrad Rzeszutek Wilk , hpa@zytor.com On Mon, Jun 02, 2014 at 03:46:10PM +0100, Jan Beulich wrote: > For cold page allocations using the normal clear_highpage() mechanism > may be inefficient on certain architectures, namely due to needlessly > replacing a good part of the data cache contents. Introduce an arch- > overridable clear_cold_highpage() (using streaming non-temporal stores > on x86, where an override gets implemented right away) to make use of > in this specific case. > > Leverage the impovement in the Xen balloon driver, eliminating the > explicit scrub_page() function. Any benchmark data? I've tried non-temporal stores to clear huge pages, but it didn't helped much. I believe it can vary between micro-architectures, but we need numbers. I've played with Westmere that time. -- Kirill A. Shutemov -- 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