From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH] eal: decrease the memory init time with many
	hugepages setup
Date: Thu, 02 Apr 2015 14:55:53 +0200
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2015-04-02 19:30, jerry.lilijun-hv44wF8Li93QT0dZR+AlfA@public.gmane.org:
> From: Lilijun <jerry.lilijun-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
> 
> In the function map_all_hugepages(), hugepage memory is truly allocated by
> memset(virtaddr, 0, hugepage_sz). Then it costs about 40s to finish the
> dpdk memory initialization when 40000 2M hugepages are setup in host os.

Yes it's something we should try to reduce.

> In fact we can only write one byte to finish  the allocation.

Isn't it a security hole?

This article speaks about "prezeroing optimizations" in Linux kernel:
	http://landley.net/writing/memory-faq.txt