From: Tim Shepard <shep@alum.mit.edu>
To: linux-usb-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org
Subject: Re: (2.6.0-test9) usb_storage/uhci_hcd much slower write than linux-2.4
Date: Mon, 03 Nov 2003 17:17:25 -0500 [thread overview]
Message-ID: <200311032217.hA3MHPWB012429@ginger.lcs.mit.edu> (raw)
In-Reply-To: Your message of Sat, 01 Nov 2003 23:03:33 -0500.
Someone sent me a private e-mail message suggesting that I apply this
patch that Matthew Dharm posted to the linux-usb-devel list yesterday
and see if that would restore the write throughput to linux-2.4
levels.
The patch limits the size of the transfers, and can be found at
http://sourceforge.net/mailarchive/message.php?msg_id=6429200
or right here:
--- drivers/usb/storage/scsiglue.c.orig 2003-08-09 00:36:46.000000000 -0400
+++ drivers/usb/storage/scsiglue.c 2003-11-03 16:49:42.000000000 -0500
@@ -315,6 +315,9 @@
/* lots of sg segments can be handled */
.sg_tablesize = SG_ALL,
+ /* limit the total size of a transfer to 120 KB */
+ .max_sectors = 240,
+
/* merge commands... this seems to help performance, but
* periodically someone should test to see which setting is more
* optimal.
I am happy to report that this patch has restored the write throughput
to the same speed that it was on linux-2.4.
Problem solved. Thanks much.
-Tim Shepard
next reply other threads:[~2003-11-03 22:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-03 22:17 Tim Shepard [this message]
-- strict thread matches above, loose matches on Subject: below --
2003-11-02 4:03 Tim Shepard
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=200311032217.hA3MHPWB012429@ginger.lcs.mit.edu \
--to=shep@alum.mit.edu \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb-devel@lists.sourceforge.net \
/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
all inboxes | Powered by JetHome®