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To: John-Mark Gurney <jmg@funkthat.com>
Subject: Re: always load aesni or load it when cpu supports it
In-reply-to: <20131021164034.GU56872@funkthat.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <20131020070022.GP56872@funkthat.com>
 <423D921D-6CE5-49D9-BCED-AB14EB236800@grondar.org>
 <20131020161634.GQ56872@funkthat.com> <5264F074.4010607@freebsd.org>
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Date: Mon, 21 Oct 2013 18:22:08 +0000
Message-ID: <37693.1382379728@critter.freebsd.dk>
Cc: Andre Oppermann <andre@freebsd.org>, Mark R V Murray <mark@grondar.org>,
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In message <20131021164034.GU56872@funkthat.com>, John-Mark Gurney writes:

>The choice of 32 blocks (512 bytes) was arbitrary, but chosen because
>it is a disk sector size...  If you're doing that much AES, on a slower
>machine, you'll probably want to use an accelerator...

I'd say it is both arbitrary and pointless.

Logical "disk-sectors" under both GBDE and GELI can be any size
(think RAID-5 stripe) and consumer harddisks have 4K sectors these days.

Why do you fee a limit is necessary ?

-- 
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.