[Asterisk-Users] four wildcards in a single pc

[Steven Critchfield]

On Thu, 2004-12-09 at 14:23 +0200, Shoval Tomer wrote:
> Hi.
> Please excuse me asking this again. But it really puzzles me.

Asking multiple times does not change a proper answer. 

> We're installing asterisk at a branch office at NJ (HQ is at
> Petach-Tikva)
> It'll need to support 5 POTS lines, 11 analog extensions and four VOIP
> phones.
> 
> I wanted to go with a T1 card from digium and a channel bank, but we
> have a dead line. It has to be up and running by January 1st.
> I don't have the time to start shopping at ebay, where you don't know
> what you'll get, and you need to install, under time pressure something
> you not familiar with.

Then why don't you buy a new channel bank? They are available but a bit
costly. You know you will get a good device and no time frame.

Of course for ebay...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=51279&item=5737077189&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=51268&item=5736884544&rd=1

And these 2 FXO cards.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=51279&item=5736458763&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=67286&item=5735996388&rd=1

> So I thought of installing a combination of four pci cards in the
> machine, and everybody on the list just keeps telling me it won't work.
> 
> I have installed successfully more then four cards in a machine before.
> I had a firewall with eight network interfaces (one quad card, one duo
> and two singles)
> I have machines with two dialogic boards, a pci display card, and a
> network interface.
> And I know I've had machines at home that had a display adaptor, modem,
> network, scsi, and soundblaster all together.
> 
> Yet, people claim it won't work because of lack of IRQs, and that it's
> not related to Digium.

You need to understand that the Digium cards generate 1000 interupt
requests per second per card. So 4 Digium cards generate 4000 interupts
per second. Your system will start to buckle under the load if you had
enough of a computer to begin with.

Your other experiences had not been with a device that needed realtime
access. For example with your network cards, they are all packet based
and if the packet isn't received or acked, it just gets resent. For your
other deployment, the SCSI card doesn't need realtime access as it can
be buffered, video isn't realtime, modem needs faster access if it is
winmodem but not otherwise, and the soundcard is real low interupt
count, and the network card follows the above example.

You should some time build a system for analog video capture on 7 year
old hardware or worse to be under the performance gun. 
-- 
Steven Critchfield <critch at basesys.com>