[Asterisk-Users] PCI front mount chassis?

[Rich Adamson]

> Looking at my /proc/interrupts:
> 
>   0:   59709041          XT-PIC  timer
>   5:  597050409          XT-PIC  wcfxo
>   7:  597211339          XT-PIC  wcfxo
>  10:    4538876          XT-PIC  eth0
>  11:    3044608          XT-PIC  aic7xxx, eth1
> 
> The voice cards generate an order of magnitude more interrupts than
> anything else. This "may" be why it's not recommended to share
> interrupts on voice cards. Don't know if the T1 cards have a similar
> issue. I would hope not. The x100p's are a pretty simplistic device.
> They probably generate an interrupt for every byte. The x100p's are also
> used for timing in things like MOH and MM conferences AFAIK. It seems
> like it would be nice to only put one card in "timer mode" if that is
> indeed what is generating all those interrupts. Could someone "in the
> know" enlighten us?

The x100p incurres roughly 1000 interrupts per second. Someone on the list
published a short unix command-line that essentially ran the above twice
and calculated the interrupts / sec nicely. It was kind of a handy way
to visually inspect the numbers to diagnose problems/issues. If I recall, 
that was around early/mid 2003 in the archives.

I believe that "is" the zap timing referred to frequently relative to
"do you have a zap card installed".

Anyway, balancing the processing required per card verses how many cards
can share an interrupt is a system engineering task (regardless of
what the cards are doing). However, that engineering task is complicated
by the lack of published _actual_ requirements/expectations for each type
of card that can be installed/supported, and therefore raises questions 
(and some spontaneous off-the-wall responses) that aren't necessarily
based on facts.

Rich