From: Scott Long <scott_long@adaptec.com>
To: Ricky Beam <jfbeam@bluetronic.net>
Cc: Michael <michael@insulin-pumpers.org>, linux-raid@vger.kernel.org
Subject: Re: 3ware escalade vs software raid, from a different jeff
Date: Thu, 19 Feb 2004 15:33:59 -0700 [thread overview]
Message-ID: <403539D7.30202@adaptec.com> (raw)
In-Reply-To: <Pine.GSO.4.33.0402191508420.28488-100000@sweetums.bluetronic.net>
Ricky Beam wrote:
> On Thu, 19 Feb 2004, Michael wrote:
> >Bear in mind that what you are calling "true hardware raid" is really
> >a microprocessor programmed to do the raid algorithims.
>
> 3ware has custom designed matrix switch chips to handle each IDE drive.
> This *alone* is worth the cost of the card. The RAID parity calculations
> are also done in hardware (not a bunch of CPU xor's.) You'd be
> surprised how
> much data a small "slow" processor can move when properly programmed.
>
Are you talking about host-processor XOR or adapter card XOR? The i960
processor used in practically every RAID card known to man right now has
an XOR engine in the memory controller. It's not quite as efficient as
some higher-end implementations, but it's a heck of a lot better than
having that i960 core spin through an XOR software loop.
Scott
next prev parent reply other threads:[~2004-02-19 22:33 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-02-18 21:48 3ware escalade vs software raid, from a different jeff Rev. Jeffrey Paul
2004-02-18 22:58 ` Jeff Garzik
2004-02-19 11:49 ` Holger Kiehl
2004-02-19 12:06 ` Joshua Baker-LePain
2004-02-19 17:56 ` Rev. Jeffrey Paul
2004-02-19 19:58 ` Michael
2004-02-19 20:18 ` Ricky Beam
2004-02-19 22:04 ` Scsi adapters and software raid Bob Hillegas
2004-02-20 0:33 ` Kanoa Withington
2004-02-20 4:27 ` Jeff Garzik
2004-02-19 22:33 ` Scott Long [this message]
2004-02-19 23:52 ` 3ware escalade vs software raid, from a different jeff Guy
2004-02-19 22:29 ` Scott Long
2004-02-20 4:26 ` Jeff Garzik
2004-02-20 4:40 ` Scott Long
2004-02-20 0:38 ` Jeff Garzik
2004-02-20 7:19 ` Joshua Baker-LePain
2004-02-19 12:11 ` Måns Rullgård
2004-02-19 12:32 ` Holger Kiehl
2004-02-19 12:32 ` Jeff Garzik
-- strict thread matches above, loose matches on Subject: below --
2004-02-23 22:23 Jeff Gray
2004-02-24 8:06 ` Holger Kiehl
2004-02-24 14:16 ` Joshua Baker-LePain
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=403539D7.30202@adaptec.com \
--to=scott_long@adaptec.com \
--cc=jfbeam@bluetronic.net \
--cc=linux-raid@vger.kernel.org \
--cc=michael@insulin-pumpers.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).