Amavis 2.10.1 dies and is unusable when put under moderate load

[Mark Martinec]

Quanah,

> We recently updated to Amavisd 2.10.1 from 2.9.0 internally, and have 
> found that amavisd
> constantly dies while processing messages after being put under a 
> moderate load in our
> QA environment.
> 
> Jan 19 06:57:52 zqa-211 amavis-services[18544]: PID 13724 went away, 
> 13724-01

The process crashed. This is typically due to execution of some perl 
module
with embedded C code, or linked to some external library which crashed
a perl process. A less likely cause could be running into some resource
limit, unhandled by perl.

> Jan 21 07:01:24 zqa-211 amavis[4970]: (04970-01-6) get_deadline 
> do_ascii_pre - deadline in 479.9 s, set to 288.000 s
> Jan 21 07:01:24 zqa-211 amavis[4970]: (04970-01-6) prolong_timer 
> do_ascii_pre: timer 288, was 0, deadline in 479.9 s
> 
> Then we see (all together):
> Jan 21 07:01:34 zqa-211 amavis-services[6954]: PID 3480 went away, 
> 03480-01-25
> Jan 21 07:01:34 zqa-211 amavis-services[6954]: PID 4970 went away, 
> 04970-01-6
> Jan 21 07:01:34 zqa-211 amavis-services[6954]: PID 2609 went away, 
> 02609-01-31
> Jan 21 07:01:36 zqa-211 amavis-services[6954]: PID 5406 went away, 
> 05406-01
> Jan 21 07:01:38 zqa-211 amavis-services[6954]: PID 5416 went away, 
> 05416-03
> Jan 21 07:01:38 zqa-211 amavis-services[6954]: PID 5421 went away, 
> 05421-01
> 
> I.e., every single one of the above processes are in the same function.

There you go, the problem must be in do_ascii - which calls 
Convert::UUlib,
which in turn uses the uulib library - which has been known to cause 
crashes
in the past. It is ancient library, poorly maintained.

The do_ascii has been removed (commented out) from a default @decoders 
list
(I believe in amavisd 2.9.0). I suggest to remove it from your @decoders
list in the config file, it causes more grief than is worth.

   Mark