[Dovecot] many instances om imap and imap-login

[Dominic Marks]

On Tuesday 26 April 2005 14:58, Jon wrote:
> Hi,
>
> Im using dovecote as my IMAP interface. However i do have a lot of imap
> instances. its only 7 user using the system as i get this. please advice.

Having lots of processes running isn't automatically a bad thing, but you do 
seem to have quite a lot of imap and imap-login processes, so:

From a dovecot.conf on a server I run being used by about 7 people:
 (Comments are from dovecot-sample.conf)

# Should each login be processed in it's own process (yes), or should one
# login process be allowed to process multiple connections (no)? Yes is more
# secure, espcially with SSL/TLS enabled. No is faster since there's no need
# to create processes all the time.
login_process_per_connection = no

So if security is less of a concern than having many processes running, you 
should set this to no.

# Number of login processes to create. If login_process_per_user is
# yes, this is the number of extra processes waiting for users to log in.
login_processes_count = 1

I set this low because I don't need the extra processes.

# Maximum number of extra login processes to create. The extra process count
# usually stays at login_processes_count, but when multiple users start 
# logging in at the same time more extra processes are created. To prevent
# fork-bombing we check only once in a second if new processes should be
# created - if all of them are used at the time, we double their amount until
# limit set by this setting is reached. This setting is used only if
# login_process_per_use is yes.
#login_max_processes_count = 128

You might want to set this to something like 4?

# Maximum number of connections allowed in login state. When this limit is
# reached, the oldest connections are dropped. If login_process_per_user
# is no, this is a per-process value, so the absolute maximum number of users
# logging in actually login_processes_count * max_logging_users.
#login_max_logging_users = 256

Probably no need to worry about this.

> 1230 ?        S      0:00 imap-login
>  1309 ?        S      0:00 imap-login

 <snip>

>  2387 ?        S      0:00 imap-login 3095 ?        S      0:00 imap
>  3096 ?        S      0:00 imap-login
>
> /jon

Other things to think about:

Are the mailboxes being accessed via Webmail?
What Mail application are your users using?
Have you checked what state the connections are in?

HTH,
-- 
Dominic
GoodforBusiness.co.uk
I.T. Services for SMEs in the UK.