Message-ID: <44705F38.10905@argo.co.il>
Date: Sun, 21 May 2006 15:38:16 +0300
From: Avi Kivity <avi@argo.co.il>
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To: Jeff Dike <jdike@addtoit.com>
CC: Renzo Davoli <renzo@cs.unibo.it>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Andi Kleen <ak@suse.de>, Daniel Jacobowitz <dan@debian.org>,
       Ulrich Drepper <drepper@gmail.com>, osd@cs.unibo.it,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 2-ptrace_multi
References: <20060518155337.GA17498@cs.unibo.it> <20060519174534.GA22346@cs.unibo.it> <20060519201509.GA13477@nevyn.them.org> <200605192217.30518.ak@suse.de> <1148135825.2085.33.camel@localhost.localdomain> <20060520183020.GC11648@cs.unibo.it> <20060520213959.GA4229@ccure.user-mode-linux.org>
In-Reply-To: <20060520213959.GA4229@ccure.user-mode-linux.org>
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Jeff Dike wrote:
>> PTRACE_MULTI can be also used to optimize many other virtualized calls,
>> e.g. to read/write all the buffers for a readv/writev/recvmsg/sendmsg
>> call at once.
>>     
>
> Here, I bet the data copying cost dominates the system call, and the
> syscall overhead is minimal.	

In addition, the aio API allows you to do that in two calls for an iovec 
of any size.

-- 
error compiling committee.c: too many arguments to function

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