From: Stan Hoeppner <stan@hardwarefreak.com>
To: xfs@oss.sgi.com
Subject: Re: xfs_fsr question for improvement
Date: Fri, 16 Apr 2010 05:43:49 -0500 [thread overview]
Message-ID: <4BC83F65.4040309@hardwarefreak.com> (raw)
In-Reply-To: <201004161043.11243@zmi.at>
Michael Monnerie put forth on 4/16/2010 3:43 AM:
> To prevent this, xfs_fsr should do a "compress" phase after
> defragmentation finished, in order to move all the files behind each
> other:
> file 1GB
> file 1GB
> file 1GB
> file 1GB
> freespace 3600M
> That would also help fill the filesystem from front to end, reducing
> disk head moves.
What happens if those are frequently written/appended files, such as logs or
mbox mail files, database files, etc? If you pack them nose to tail with
this "compress" phase they will instantly be fragmented upon the next append
operation. Leaving some free sectors at the tail end of a file is what
helps prevent fragmentation. I don't think this compression would be a good
default behavior. I think "packing" is probably a better term as
"compression" has a long standing connotation.
Sounds like you have a corner case. If this "packing" was implemented,
maybe it would be best to make it a command line option only.
--
Stan
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next prev parent reply other threads:[~2010-04-16 10:41 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-16 8:43 xfs_fsr question for improvement Michael Monnerie
2010-04-16 10:43 ` Stan Hoeppner [this message]
2010-04-17 1:24 ` Dave Chinner
2010-04-17 7:13 ` Emmanuel Florac
2010-04-25 11:17 ` Peter Grandi
2010-04-25 13:02 ` Emmanuel Florac
2010-04-25 21:04 ` Eric Sandeen
2010-04-25 21:44 ` Emmanuel Florac
2010-04-26 0:02 ` Linda Walsh
2010-05-03 6:49 ` Michael Monnerie
2010-05-03 7:41 ` Michael Monnerie
2010-05-03 12:17 ` Dave Chinner
2010-05-10 22:39 ` Michael Monnerie
-- strict thread matches above, loose matches on Subject: below --
2010-04-26 20:58 Richard Scobie
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=4BC83F65.4040309@hardwarefreak.com \
--to=stan@hardwarefreak.com \
--cc=xfs@oss.sgi.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox