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Date: Wed, 25 Nov 2015 09:57:08 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 2/2] lib/librte_eal: Remove unnecessary
 hugepage zero-filling
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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 <thomas.monjalon@6wind.com> wrote:
> > 
> > > 2015-11-22 18:28, Stephen Hemminger:
> > > > On Sun, 22 Nov 2015 14:13:35 -0500
> > > > Zhihong Wang <zhihong.wang@intel.com> 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 <zhihong.wang@intel.com>
> > > > 
> > > > Nice, especially on slow machines or with large memory.
> > > > 
> > > > Acked-by: Stephen Hemminger <stephen@networkplumber.org>
> > > 
> > > 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