> This is interesting because I have a linux box (RedHat AS3) using > RAID 10. I > have some 5000 user accounts and anywhere from 2500 to 3000 > concurrent IMAP > sessions -- I think the Mulberry client opens multiple sessions since it's > only some 300 to 500 individual concurrent users. Anyway, what I > especially > notice is that when the mail delivery queue on the MTA gets very > large, which > happens occassionally, the CPU load average goes way up and iowait time as > displayed using top can exceed 300% on a four processor box and > performance > goes all to heck. Is switching the filesystem to XFS likely to help this > situation? Since there is some 80GB of mail spool currently in use, > switching the filesystem to XFS is not a simple task and I don't > won't to do > it on a lark. > > Thanks, > Rob >
I feel that XFS is a bad choice since it is not a 'truly' journaled file system. If you have a power failure/system crash/lockup, etc., etc. You could very easily end up with a corrupt file system -- XFS doesn't write out to the disks immediately (caching unwritten data to memory). EXT3 is journaled but very slow. ReiserFS is a better choice for a journaled file system and if you can hold off until all the bugs are worked out, Reiser4FS would be the best choice (IMHO). Jim --- Cyrus Home Page: http://asg.web.cmu.edu/cyrus Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html