> -----Original Message----- > From: Thomas Monjalon [mailto:thomas.monjalon at 6wind.com] > Sent: Wednesday, November 25, 2015 7:04 AM > To: Stephen Hemminger <stephen at networkplumber.org> > Cc: Wang, Zhihong <zhihong.wang at intel.com>; dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH 2/2] lib/librte_eal: Remove unnecessary > hugepage zero-filling > > 2015-11-24 14:44, Stephen Hemminger: > > On Tue, 24 Nov 2015 22:13:28 +0100 > > Thomas Monjalon <thomas.monjalon at 6wind.com> wrote: > > > > > 2015-11-22 18:28, Stephen Hemminger: > > > > On Sun, 22 Nov 2015 14:13:35 -0500 Zhihong Wang > > > > <zhihong.wang at 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 at intel.com> > > > > > > > > Nice, especially on slow machines or with large memory. > > > > > > > > Acked-by: Stephen Hemminger <stephen at 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. > I'm asking for opinions because it would be really nice to have.
Literally this patch doesn't change anything, it just keeps DPDK from zero-filling pages again which have just been zero-filled. It would be nice to have this patch in DPDK 2.2 since it can reduce the startup time nearly by half for hugepage cases. But I understand longer merge/test window make it safer for a release. It makes sense either way.
