Date: Mon, 12 Jan 2009 23:27:26 +0300
From: Evgeniy Polyakov <zbr@ioremap.net>
To: =?utf-8?B?UsOpbWk=?= Denis-Courmont <rdenis@simphalempin.com>
Cc: Andi Kleen <andi@firstfloor.org>, Valdis.Kletnieks@vt.edu,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, Michael Stone <michael@laptop.org>,
       linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: RFC: Network privilege separation.
Message-ID: <20090112202726.GA2169@ioremap.net>
References: <1231307334-9542-1-git-send-email-michael@laptop.org> <200901122147.57731.rdenis@simphalempin.com> <20090112201435.GC23848@one.firstfloor.org> <200901122215.27842.rdenis@simphalempin.com>
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On Mon, Jan 12, 2009 at 10:15:27PM +0200, Rémi Denis-Courmont (rdenis@simphalempin.com) wrote:
> > I don't think that's given. It would need some restructuring,
> > but I think the end result would be likely worth it.
> 
> A normal DVD would be over 30 megabytes per seconds once decoded, just for the 
> video. And remember vmsplice() is not allowed by SECCOMP. Media players have 
> assembly-coded memory copy optimizations (like the kernel) for some reason.

Just a note: memory copy is way too faster than 30 mb/s, and very likely
it is not the memory copy, but (de)compression, since likely all modern
codecs are limited by the CPU and not the memory bandwidth.

-- 
	Evgeniy Polyakov
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