[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

hanging imapd processes (was Re: Runaway processes ?)

Craig Sanders wrote:

On Wed, Nov 24, 2004 at 07:15:43PM +0200, Uffe Pensar wrote:
[141 lines of quoted material deleted.  please learn to trim your quotes ]
ok thanks for all the good advices, I will install postfix and have a look att the dovecot and xinetd packages

if you're running dovecot, you don't need xineted.  it is a standalone daemon,
which has it's own (configurable) limits on maximum simultaneous connections.

but as a quick fix its seems that authenticating from a local server
(instead of radius) and restricting the number of webmailsessions has
helped for the moment. But I suppose we have to buy more servers in
the near future.

yes, separating the tasks of 1) sending & receiving mail and 2) storing it &
providing imap/pop/webmail/etc access is very useful.

remember that mail is an I/O bound system.  i.e. most of the time the processor
is sitting idle waiting for disk I/O to complete.  upgrading the CPU will do
little or no good here. to improve performance, you need to improve the I/O
speed - you can do this with faster disks, hardware raid card with large
non-volatile cache, and by adding more RAM to the system.  or by spreading the
I/O load over more disks and/or more servers.

I'm in the process of separating the webmail from the imap and I have have installed xinetd with
max_load and other limits.
But still I can't understand that i get those hanging imapd processes ?

# ps axu|grep imapd|grep root
root     22700  0.0  0.0  4064 1308 ?        S    Nov25   0:00 [imapd]
root     11359  0.0  0.0  4064 1400 ?        S    Nov27   0:00 [imapd]
root      6473  0.0  0.0  4064 1400 ?        S    Nov27   0:00 [imapd]
root      3801  0.0  0.0  4064 1400 ?        S    Nov27   0:00 [imapd]
root      6194  0.0  0.0  1752  732 pts/7    S    21:11   0:00 grep imapd

woody and uw-imap-ssl (those hanging connections are not coming from webmail)

- uffe

Reply to: