From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yuanhan Liu Subject: Re: [PATCH 2/2] lib/librte_eal: Remove unnecessary hugepage zero-filling Date: Wed, 25 Nov 2015 09:57:08 +0800 Message-ID: <20151125015708.GM2325@yliu-dev.sh.intel.com> References: <1448219615-63746-1-git-send-email-zhihong.wang@intel.com> <1640963.TLMeDD9tfp@xps13> <20151124144403.79811c0a@xeon-e3> <3179262.cyHqZdDHPg@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: dev@dpdk.org To: Thomas Monjalon Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id CE5168E8E for ; Wed, 25 Nov 2015 02:55:00 +0100 (CET) Content-Disposition: inline In-Reply-To: <3179262.cyHqZdDHPg@xps13> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Wed, Nov 25, 2015 at 12:04:16AM +0100, Thomas Monjalon wrote: > 2015-11-24 14:44, Stephen Hemminger: > > On Tue, 24 Nov 2015 22:13:28 +0100 > > Thomas Monjalon wrote: > > > > > 2015-11-22 18:28, Stephen Hemminger: > > > > On Sun, 22 Nov 2015 14:13:35 -0500 > > > > Zhihong Wang wrote: > > > > > > > > > The kernel fills new allocated (huge) pages with zeros. > > > > > DPDK just has to populate page tables to trigger the allocation. > > > > > > > > > > Signed-off-by: Zhihong Wang > > > > > > > > Nice, especially on slow machines or with large memory. > > > > > > > > Acked-by: Stephen Hemminger > > > > > > Yes very nice. > > > I think it's too late to integrate this change which can have some > > > unpredictable side effects. > > > Do you agree to wait for 2.3? > > > > What side effects? Either it is zero or it is not. > > Only some broken architecture would have an issue. > > I mean it changes the memory allocator behaviour. It's not something we > want to discover a new bug just before the release. > This kind of important change must be integrated at the beginning of the > release cycle. + 1 And it could be a new feature (or highlight) of 2.3: reduced dpdk startup time by ... :) --yliu