> Tomas Kuliavas wrote: > >> >>I think bottleneck is in your filesystem. Compare directory access times >>on different filesystems. Find the one that can access directories with >>many small files faster. >> >> > This evening I set up a test. I used the same Maildir ~850MB in size > with 27k messages in my INBOX in each case. I logged into SquirrelMail > with each user three times, and took the average number of seconds > before the INBOX folder contents appeared. > > Case 1: Maildir lives on an ext2 filesystem within a RAID5 set of five > disks. This filesystem is then NFS mounted to the IMAP server. Average > time to display: 41 seconds. > Case 2: Maildir lives on a reiserfs (Reiser4) filesystem on a RAID0 set > of two disks. This filesystem is then NFS mounted to the IMAP server. > Average time to display: 64 seconds. > Case 3: Maildir lives on an ext3 filesystem on a RAID0 set of two > disks. This filesystem is local to the IMAP server. Average time to > display: 37 seconds. > > Not at all what I expected. Pretty much everyone was saying that > ReiserFS was the way to go for many small files, and yet it was by far > the slowest. Also, the effect of NFS vs. local was small. > > I can see that the entire time I'm waiting for the page to return, imapd > is pegging the CPU, so this might be CPU-bound. However, it could also > be pegging the CPU simply because the CPU has nothing else to do and can > dedicate 99.9% of its cycles to the imapd process. I would hope that > one single imap session would not bring a Xeon 2.8GHz/1GB mem to its > knees. Even still, I'll be able to compare in a couple of weeks when > the 2nd processor and another 1GB of RAM comes in for these systems. > > Now, I might just write this off and tell users "if you have folders > with 27k messages in them, prepare for horrid performance", but it's > just one of those things that you just want to make faster. :-)
1. You forgot XFS and JFS. http://oregonstate.edu/~kveton/fs/page2.php 2. maybe fam provide some performance increase http://www.courier-mta.org/?imapd.html http://oss.sgi.com/projects/fam/ -- Tomas ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click -- squirrelmail-users mailing list Posting Guidelines: http://squirrelmail.org/wiki/wiki.php?MailingListPostingGuidelines List Address: [EMAIL PROTECTED] List Archives: http://news.gmane.org/thread.php?group=gmane.mail.squirrelmail.user List Archives: http://sourceforge.net/mailarchive/forum.php?forum_id=2995 List Info: https://lists.sourceforge.net/lists/listinfo/squirrelmail-users
