[vPostMaster] weird load issue

[Wallace Winfrey]

The load on our (dual 3GHz) machine has been stuck at 70+ for the last 
hour or so. I'm running htop and sorting by CPU process, and all the 
processes are showing 0% CPU usage. We are, however, swapping like 
crazy, and there seem to be around 100 vpostmaster-owned imap processes, 
some going back as far March 12th, but a big number of them are an hour 
or two old.

We've been used to our load being really high (our monthly average is 
4.25) but for the last few days, it's been insane, the average has been 
10. I'm about to reboot the machine (hopefully that will fix it) but it 
would be nice if we could figure out what's going on here. I had been 
thinking that spamd/clamav was the culprit, and while I know they put a 
significant load on the machine, now I'm not so sure.

I've attached an lsof of an imap process that seems to have been have 
been hanging around since March 12th:


imap      17098 vpostmaster  cwd       DIR      253,0       4096 
8422481 /var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob
imap      17098 vpostmaster  rtd       DIR      253,0       4096 
   2 /
imap      17098 vpostmaster  txt       REG      253,0     339748 
2066138 /usr/libexec/dovecot/imap
imap      17098 vpostmaster  mem       REG      253,0     112168 
884763 /lib/ld-2.3.4.so
imap      17098 vpostmaster  mem       REG      253,0    1529136 
884765 /lib/tls/libc-2.3.4.so
imap      17098 vpostmaster  mem       REG      253,0      16732 
884807 /lib/libdl-2.3.4.so
imap      17098 vpostmaster  mem-R     REG      253,0      20496 
8429796 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.log.2
imap      17098 vpostmaster  mem       REG      253,0      68540 
4309131 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.tree
imap      17098 vpostmaster  mem       REG      253,0        106 
3883325 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.customflags
imap      17098 vpostmaster  mem       REG      253,0    2137348 
4309153 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.data
imap      17098 vpostmaster  mem       REG      253,0      84552 
4309128 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index
imap      17098 vpostmaster    0u     IPv6  381849948 
TCP 
intranet.cycling74.com:imap->pool-71-187-222-116.nwrknj.fios.verizon.net:49195 
(ESTABLISHED)
imap      17098 vpostmaster    1u     IPv6  381849948 
TCP 
intranet.cycling74.com:imap->pool-71-187-222-116.nwrknj.fios.verizon.net:49195 
(ESTABLISHED)
imap      17098 vpostmaster    2r      CHR        1,3 
1980 /dev/null
imap      17098 vpostmaster    3u     unix 0xf0774d80 
381850032 socket
imap      17098 vpostmaster    4u      REG      253,0      84552 
4309128 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index
imap      17098 vpostmaster    5u      REG      253,0    2137348 
4309153 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.data
imap      17098 vpostmaster    6u      REG      253,0        106 
3883325 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.customflags
imap      17098 vpostmaster    7u      REG      253,0      68540 
4309131 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.tree
imap      17098 vpostmaster    8uR     REG      253,0      20496 
8429796 
/var/spool/vpostmaster/domains/cy/cycling74.com/mailboxes/ro/rob/Maildir/.INBOX/.imap.index.log.2