gopalakrishnan kamalanathan wrote:
Hi,
I have a few question on the IMAP implementation.
1) What is the memory footprint of the DBMail IMAP.
Mmm, my main inhouse mailserver (5 heavy users with many very large mailboxes)
running dbmail2-mysql-ldap (trunk-snapshot):
[EMAIL PROTECTED]:~# ps|grep -E 'dbmail-imap|^USER'
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 27113 0.0 0.1 5992 1092 ? S Mar25 0:01
/usr/sbin/dbmail-imapd
dbmail 12441 0.0 0.1 6128 1324 ? S Mar26 0:10
/usr/sbin/dbmail-imapd
dbmail 12589 0.0 1.6 34140 14608 ? S Mar26 0:06
/usr/sbin/dbmail-imapd
dbmail 27631 0.0 0.2 9048 2260 ? S Mar27 0:00
/usr/sbin/dbmail-imapd
dbmail 30625 0.0 0.2 9912 2704 ? S Mar27 0:00
/usr/sbin/dbmail-imapd
dbmail 31331 0.0 0.2 8980 2256 ? S Mar27 0:00
/usr/sbin/dbmail-imapd
dbmail 25281 0.0 0.3 9136 2824 ? S 08:16 0:00
/usr/sbin/dbmail-imapd
dbmail 25282 0.0 0.3 9416 3508 ? S 08:16 0:00
/usr/sbin/dbmail-imapd
dbmail 26371 0.0 0.4 9564 3724 ? S 08:26 0:00
/usr/sbin/dbmail-imapd
dbmail 27128 0.0 1.5 21056 14376 ? S 08:33 0:00
/usr/sbin/dbmail-imapd
dbmail 28084 0.0 0.3 9096 2788 ? S 08:41 0:00
/usr/sbin/dbmail-imapd
dbmail 28085 0.0 0.3 9244 3344 ? S 08:41 0:00
/usr/sbin/dbmail-imapd
dbmail 28585 0.0 0.4 9596 3680 ? S 08:46 0:00
/usr/sbin/dbmail-imapd
dbmail 30798 0.0 2.8 33164 25948 ? S 09:09 0:01
/usr/sbin/dbmail-imapd
dbmail 3907 0.0 0.3 9128 2836 ? S 09:36 0:00
/usr/sbin/dbmail-imapd
dbmail 3908 0.0 1.5 21156 14424 ? S 09:36 0:00
/usr/sbin/dbmail-imapd
dbmail 3909 0.0 1.3 19684 12272 ? S 09:36 0:00
/usr/sbin/dbmail-imapd
dbmail 3910 0.0 0.2 8980 2600 ? S 09:36 0:00
/usr/sbin/dbmail-imapd
dbmail 3912 0.0 0.3 9128 3284 ? S 09:36 0:00
/usr/sbin/dbmail-imapd
dbmail 17908 0.0 0.1 6828 1796 ? S 11:24 0:00
/usr/sbin/dbmail-imapd
dbmail 17909 0.0 0.1 6828 1796 ? S 11:24 0:00
/usr/sbin/dbmail-imapd
2) What is the maximum number of simultaneous connections that the
DBMail IMAP server can handle.
A single process can handle only one connection. You can spawn as many processes
as your database backend can handle, or as your memory and cpu will suffer.
3) How many threads does the DBMail imap server create? Does it have a
fixed pool of threads or does it create new threads as and when needed
basis?
Dbmail doesn't use threads at all. It uses dynamic preforking of a pool of
child-processes. This is very similar to what apache 1.3 uses, or apache-2.0 in
it's preforking setup. So, yes: a fixed set of processes is created at startup,
and after that new processes are created or destroyed as required, depending on
the settings in the dbmail.conf file.
4) Is it possible to have multiple connections to the same mailbox?
Multiple connections to a single mailbox is no problem at all, although it
somewhat depends on your mailclient. For instance, thunderbird is quite
aggressive in it's caching of message UIDs, which means that if user A deletes
messages from a mailbox that user B has opened, thunderbird will sometimes
become confused and start showing the wrong messages in the view pane. That is
however, strictly a client issue, *not* a dbmail issue, afaik.
--
________________________________________________________________
Paul Stevens [EMAIL PROTECTED]
NET FACILITIES GROUP GPG/PGP: 1024D/11F8CD31
The Netherlands_______________________________________www.nfg.nl
