From: Tomasz Chmielewski <mangoo@wpkg.org>
To: linux-kernel@vger.kernel.org
Cc: mbroz@redhat.com, Andi Kleen <andi@firstfloor.org>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] DM-CRYPT: Scale to multiple CPUs
Date: Mon, 31 May 2010 20:47:29 +0200 [thread overview]
Message-ID: <4C040441.9020107@wpkg.org> (raw)
Milan Broz wrote:
> On 05/31/2010 06:04 PM, Andi Kleen wrote:
>> DM-CRYPT: Scale to multiple CPUs
>>
>> Currently dm-crypt does all encryption work per dmcrypt mapping in a
>> single workqueue. This does not scale well when multiple CPUs
>> are submitting IO at a high rate. The single CPU running the single
>> thread cannot keep up with the encryption and encrypted IO performance
>> tanks.
>
> This is true only if encryption run on the CPU synchronously.
>
> (Usually it is high speed SSD or dm-crypt above striped RAID where
> underlying device throughput is higher than CPU encryption speed.)
Quite common to hit on a netbook/laptop with encrypted root these days,
where storage can be relatively fast when compared to the speed of one
of the cores of the (usually) multicore CPU.
--
Tomasz Chmielewski
http://wpkg.org
next reply other threads:[~2010-05-31 18:57 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-05-31 18:47 Tomasz Chmielewski [this message]
2010-06-01 7:21 ` [PATCH] DM-CRYPT: Scale to multiple CPUs Andi Kleen
-- strict thread matches above, loose matches on Subject: below --
2010-05-31 16:04 Andi Kleen
2010-05-31 16:34 ` Eric Dumazet
2010-05-31 17:46 ` Andi Kleen
2010-05-31 17:52 ` Eric Dumazet
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4C040441.9020107@wpkg.org \
--to=mangoo@wpkg.org \
--cc=andi@firstfloor.org \
--cc=eric.dumazet@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mbroz@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox