[RFC] Conffiguration variable for setting maximum incoming messages queue length

Hi List,

There have been some high stress Kannel tests (continous 350 msg/s, peak
560 
msg/s) here at Wiral. Kannel will crash, because incoming messages queue
will 
grow without any limits (currently it has 13000 msg and is growing), and
take 
rest of system with it.

So I think we need a upper limit here (for handling short peaks, a
smallish 
incoming messages queue is usefull). This would not apply, there are no
outgoing
messages.

Value -1, the default, would mean that infinite queues are allowed
(reasonable
with not so high loads). 0 would mean giving a strict priority to
outgoing messages, as Kalle suggested before.

Tests with queue length 0 will mean that Kannel can actually handle all
these
messages, not only queue them.

any comments ?

Aarno