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To: Julian Elischer <julian@elischer.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Fri, 21 Mar 2008 18:53:06 MST."
	<47E46682.4020403@elischer.org> 
Date: Sat, 22 Mar 2008 07:31:47 +0000
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Sender: phk@critter.freebsd.dk
Cc: Barney Cordoba <barney_cordoba@yahoo.com>, current@freebsd.org
Subject: Re: kvm_read() vs ioctl performance 
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In message <47E46682.4020403@elischer.org>, Julian Elischer writes:

>>> tried a shared memory page?
>> 
>> No, but I built a test and kvm_read is 70 times
>> faster, in
>> case anyone is interested.

The shared memory approach is much better than that, you should
go that way.

Look at the adlink driver for an example.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.