There is no question, XFS and JFS have better perf than ext3. However, in your particular problem, i would look at the FS performances as a last resort. What about the general IO of this box ? (hdd quality , bus speed , etc..etc..). Againm 500 files operations a minute does not sounds to me as a real big load (if it was a second then yes ;), so the only thing i'm saying is that the problem may be somewhere else.
JeF On Wed, 2003-02-12 at 08:57, Thedore Knab wrote: > I am not talking about huge delays but rather occasional 2-5 second delays. > > I am using Courier IMAP with the Ext3 file-system and kernel quotas. > > Postfix is delivering the Maildir file to the users' space. > > The way Courier IMAP works is each mail becomes a separate '.imap' file. > > Depending on the file's state, it goes into a different directory. > > For example, when a new mail comes in it goes to, Maildir/.new > > When it has been viewed it moves from Maildir/.new to Maildir/.cur. > > If I put files in my personal directory they end up in > Maildir/.Personal/.cur. > > Since I have about 200 - 250 people logged in during peak periods on a > dual 700Mhz machine that is mostly idle 95% of the time (except for > the off peak hour backups and quota indexing), it appears that > the file-system must be the bottleneck. > > I calculate that Courier IMAP is moving about 200-500 files every minute > during the delays. > > Additionally, mail is coming in at the rate of 100-300 messages per minute. > > Since ext3 is built on top of ext2, it adds a lot of overhead. > > The kernel quotas add more overhead. > > Although it is easy to move from ext2 to ext3, it does not offer > any greater read or write performance. > > In this month's Linux Journal, for example, > there is an article about the new SGI 64 bit machine. One thing that they used for > metrics was the file-system. According the article both ext2 and xfs > performed about the same on the 'super server'. Reiser and ext3 both performed > about 1/4 that of ext2. > > Since the system is not being taxed in any other noticeable way > according to sar, I feel that the file-system must be the bottleneck. > More specifically, it has to be ext3 or the quotas with ext3. > > > On Wed, Feb 12, 2003 at 08:16:47AM +1100, Jean-Francois Dive wrote: > > Hi, > > > not that i ever tested any of those 2 new file-system, but i have some > > troubles to believe that the FS'd be the bottleneck in your scenario; > > maybe i'm wrong, and 'd be interested to read some tests too though. > > JeF > > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] -- -> Jean-Francois Dive --> [EMAIL PROTECTED] There is no such thing as randomness. Only order of infinite complexity. - Marquis de LaPlace - deterministic Principles - -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
