linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andreas Klauer <Andreas.Klauer@metamorpher.de>
To: Marc MERLIN <marc@merlins.org>
Cc: linux-raid@vger.kernel.org
Subject: Re: md raid5 on top of dmcrypt, or dmcrypt on top of md raid5?
Date: Thu, 11 Feb 2016 18:13:40 +0100	[thread overview]
Message-ID: <20160211171340.GA7664@EIS> (raw)
In-Reply-To: <20160211162959.GG13969@merlins.org>

> gargamel:~# cryptsetup luksDump /dev/md8
> LUKS header information for /dev/md8
> 
> Version:        1
> Cipher name:    aes
> Cipher mode:    xts-plain64
> Hash spec:      sha1
> Payload offset: 3072
> MK bits:        256

Does the box have AES-NI? What's your 'cryptsetup benchmark' look like?
Sometimes there can be a problem if the AES-NI module is loaded too late.
Without AES-NI your performance will suffer either way... 

You probably don't want encryption below the RAID; that would mean 
encrypting redundancy and parity so it's even more work to do, doubtful 
whether multicore CPU can offset that to make it worth it. Maybe if 
it's a NAS that has nothing else to do...

Regards
Andreas

  reply	other threads:[~2016-02-11 17:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-11 16:29 md raid5 on top of dmcrypt, or dmcrypt on top of md raid5? Marc MERLIN
2016-02-11 17:13 ` Andreas Klauer [this message]
2016-02-11 17:40   ` Marc MERLIN
2016-02-12  9:30 ` Mikael Abrahamsson
2016-02-12 14:34   ` Jes Sorensen
2016-02-12 19:07     ` Marc MERLIN
2016-02-12 19:57       ` John Stoffel
2016-02-22  0:44         ` Marc MERLIN

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=20160211171340.GA7664@EIS \
    --to=andreas.klauer@metamorpher.de \
    --cc=linux-raid@vger.kernel.org \
    --cc=marc@merlins.org \
    /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;
as well as URLs for NNTP newsgroup(s).