From: Pierre Ossman <drzeus-list@drzeus.cx>
To: LKML <linux-kernel@vger.kernel.org>,
Russell King <rmk+lkml@arm.linux.org.uk>
Subject: MMC performance
Date: Mon, 11 Oct 2004 13:05:09 +0200 [thread overview]
Message-ID: <416A68E5.6080608@drzeus.cx> (raw)
I've added SGIO support to my driver now hoping that it would resolve
the piss-poor performance I've been getting. Didn't do much difference
though.
Read operations are fairly fast. It queues 8kB at a time. A bit small
perhaps, but still decent.
Writing, however, only sends a single sector at a time. The queue
process eats up half of the CPU time on my machine during a write. And
since MMC cards have to clear a whole bunch of sectors before a write
shouldn't you send as many sectors as possible to them?
Since I don't have another controller to compare with I don't really
know if the problem is in my code, the MMC layer, the block layer or the
filesystem.
I'm going to dig around a bit more but some pointers are welcome. At
least which layer I should be looking at.
Rgds
Pierre
next reply other threads:[~2004-10-11 11:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-10-11 11:05 Pierre Ossman [this message]
2004-10-11 12:19 ` MMC performance Russell King
2004-10-11 13:18 ` Alan Cox
2004-10-11 15:27 ` Pierre Ossman
2004-10-11 18:01 ` Pierre Ossman
2004-10-18 19:26 ` Pierre Ossman
2004-10-11 13:49 ` Pierre Ossman
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=416A68E5.6080608@drzeus.cx \
--to=drzeus-list@drzeus.cx \
--cc=linux-kernel@vger.kernel.org \
--cc=rmk+lkml@arm.linux.org.uk \
/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