[Dovecot] load-based control of dovecot?

[Jeff A. Earickson]

Timo,
    If you don't mind "borrowing" code, take a look at the getla()
routines in conf.c of the public-domain sendmail.  This file
uses a bunch of "peer into the kernel for load statistics" calls
for various versions of unix, eg "kstat(3KSTAT)" for Solaris
and pstat_dynamic() for HPUX.

   getla() queries the kernel for the current load, then sleeps
or refuses connections for a brief period until the load drops.
Just a suggestion.

Jeff Earickson
Colby College

On Fri, 28 Oct 2005, Timo Sirainen wrote:

> Date: Fri, 28 Oct 2005 22:11:19 +0300
> From: Timo Sirainen <tss at iki.fi>
> To: Jeff A. Earickson <jaearick at colby.edu>
> Cc: dovecot at dovecot.org
> Subject: Re: [Dovecot] 1.0alpha3: fcntl() complaints?
> 
> On Tue, 2005-09-27 at 17:31 -0400, Jeff A. Earickson wrote:
>> Is there any kind of load-based control, like sendmail uses, that
>> would reject connections if "uptime" load > N?
>
> That could be useful, but I'm not really sure what would be a good way
> to implement it. Maybe if some file exists
> (/var/run/dovecot/no-connections or something?) and Dovecot master
> process notices it, it stops accepting new imap/pop3 connections? The
> file would then be created by some script you're running that checks the
> load. And I think that file should be deleted when Dovecot is started,
> so that people don't wonder why Dovecot isn't working.
>
>