From: Dan Williams <dan.j.williams@intel.com>
To: neilb@suse.de, akpm@linux-foundation.org
Cc: raziebe@gmail.com, linux-raid@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [-mm PATCH 0/2] 74% decrease in dispatched writes, stripe-queue take3
Date: Fri, 13 Jul 2007 15:35:42 -0700 [thread overview]
Message-ID: <20070713223257.25202.74399.stgit@dwillia2-linux.ch.intel.com> (raw)
Neil, Andrew,
The following patches replace the stripe-queue patches currently in -mm.
Following your suggestion, Neil, I gathered blktrace data on the number
of reads generated by sequential write stimulus. It turns out that
reduced pre-reading is not the cause of the performance increase, but
rather increased write merging. The data, in patch #1, shows a 74%
decrease in the number of dispatched writes. I can only assume that
this is the explanation for the 65% throughput improvement, because the
occurrence of reads actually increased with these patches applied.
This take also fixes observed data corruption while running i/o to a
synching array (it was wrong to move the flags parameter from r5dev to
r5_queue_dev as things could get out of sync... reverted). Next step is
to test reshape under this new queuing model.
Regards,
Dan
next reply other threads:[~2007-07-13 22:35 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-07-13 22:35 Dan Williams [this message]
2007-07-13 22:35 ` [-mm PATCH 1/2] raid5: add the stripe_queue object for tracking raid io requests (take2) Dan Williams
2007-07-13 22:35 ` [-mm PATCH 2/2] raid5: use stripe_queues to prioritize the "most deserving" requests (take3) Dan Williams
2007-07-13 22:54 ` [-mm PATCH 0/2] 74% decrease in dispatched writes, stripe-queue take3 Andrew Morton
2007-07-13 22:57 ` Williams, Dan J
2007-07-13 22:57 ` Williams, Dan J
2007-07-13 23:01 ` Andrew Morton
2007-07-13 23:01 ` Andrew Morton
2007-07-13 23:28 ` Williams, Dan J
2007-07-13 23:28 ` Williams, Dan J
2007-07-14 0:01 ` Andrew Morton
2007-07-14 0:01 ` Andrew Morton
2007-07-14 0:14 ` mutex_unlock() in interrupt context Jerry Cooperstein
2007-07-17 7:01 ` Andrew Morton
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=20070713223257.25202.74399.stgit@dwillia2-linux.ch.intel.com \
--to=dan.j.williams@intel.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=neilb@suse.de \
--cc=raziebe@gmail.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.