From: Dmitry Potapov <dpotapov@gmail.com>
Date: Mon, 22 Feb 2010 13:33:27 GMT
Subject: Re: [PATCH] Teach "git add" and friends to be paranoid
Message-ID: <20100222133327.GH10191@dpotapov.dyndns.org>
In-Reply-To: <4B827FC6.1090905@gnu.org>

On Mon, Feb 22, 2010 at 01:59:50PM +0100, Paolo Bonzini wrote:
> On 02/18/2010 06:36 AM, Junio C Hamano wrote:
> >
> >In any case, with any size of paranoia, this hurts the sane use case
> 
> Because by mmaping + memcpying you are getting the worst of both
> cases: you get a page fault per page like with mmap, and touch
> memory twice like with read.

and there is also an extra round of SHA-1 calculation, which I believe
is more expensive than memcpy().


Dmitry