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Date: Sat, 28 Feb 2009 13:58:16 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Salman Qazi <sqazi@google.com>, davem@davemloft.net,
       linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
       "H. Peter Anvin" <hpa@zytor.com>, Andi Kleen <andi@firstfloor.org>
Subject: Re: [patch] x86, mm: pass in 'total' to __copy_from_user_*nocache()
Message-ID: <20090228125816.GA14917@elte.hu>
References: <20090224020304.GA4496@google.com> <200902272305.01867.nickpiggin@yahoo.com.au> <20090228082922.GB11425@elte.hu> <200902282249.57479.nickpiggin@yahoo.com.au>
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* Nick Piggin <nickpiggin@yahoo.com.au> wrote:

> > It might be wrong on the principle though, so will revert it 
> > if needed, before it spreads into too many topics.
> 
> I would say if Linus didn't like it, revert it.
> 
> Do you use NFS with 1500 byte packets with a high speed 
> network and really fast disks (or ramdisk)? Then maybe you can 
> measure vectored write speedup with your patch over Salman's 
> more basic one :)

Can you suggest some other workload that should show sensitivity 
to this detail too? Like a simple write() loop of non-4K-sized 
files or so?

	Ingo