[Asterisk-Users] four wildcards in a single pc

[Gilad Ben-Yossef]

Hi Jim,

Jim Van Meggelen wrote:


> Getting dedicated IRQs for the cards is a minor problem compared to what
> happens when you have four cards hammering away mercilessly at the
> chipset and CPU of your motherboard; 1000 IRQs per second, per card.
> Nobody's really sure what's wrong, but it causes problems for pretty
> nearly everyone.

 From your description it is very clear what is wrong - the machine is 
heavily over loaded (or sometime having load spikes) due to interrupt 
livelock. It spends so much resources dealing with interrupts that it 
doesn't have enough CPU time to handle any thing else.

If anyone is interested in a very more info about this phenomena, simply 
search google for "interrupt livelock" and "interrupt mitigation". Most 
of the research pertaining to this problem was done for network cards 
but it really applies to any source of (too many) interrupts.

I've had some expereicne dealing with the problem in network cards. If I 
can help in any way...

Cheers,
Gilad


-- 
Gilad Ben-Yossef <gilad at codefidence.com>
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