asterisk users - Jun 2009 - Scaling

Hi,

Quick question to the real world.

Approx what specs would I need on server to handle 95 ZAP or Dahdi -> SIP
gateway using G729 on the SIP to carrier side (nothing else, just media
conversion)?

Does the latest Asterisk/DAHDI significantly improve these numbers over say,
Asterisk 1.2.X?

Sure, there is plenty to read but nothing I could find quickly on my exact
needs that was clear and I want to be fairly sure before ordering a server.

Obviously load avg has something to do with it but CPU and mem seems to be
the biggest factors.

-- 
Thanks,
Steve Totaro
+18887771888 (Toll Free)
+12409381212 (Cell)
+12024369784 (Skype)
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.digium.com/pipermail/asterisk-users/attachments/20090617/c4280a82/attachment.htm

On Wed, 17 Jun 2009, Steve Totaro wrote:
> Hi,
>
> Quick question to the real world.
>
> Approx what specs would I need on server to handle 95 ZAP or Dahdi ->
SIP
> gateway using G729 on the SIP to carrier side (nothing else, just media
> conversion)?
>
> Does the latest Asterisk/DAHDI significantly improve these numbers over
say,
> Asterisk 1.2.X?
>
> Sure, there is plenty to read but nothing I could find quickly on my exact
> needs that was clear and I want to be fairly sure before ordering a server.
>
> Obviously load avg has something to do with it but CPU and mem seems to be
> the biggest factors.
Transcoding - It's CPU grunt and multi processors what you need (more so 
than memory) - handling that many calls ought to be a breeze on any modern 
hardware without the transcoding. Personally, I think I'd be looking at a 
TC400B card which can handle 96 concurrent g729 transcodes...

But as a rough benchmark, I can do 12 concurrent g729 transcodes on a 1GHz 
VIA processor before it's totally maxed out, (stupid) extrapolation to 96 
would suggest 8 x 1GHz processors, 4 x 2GHz, or 3 x 3GHz processors... 
However you gain more with the faster processors in terms of bigger cache 
(but that can also be a loss too) I'd start with a quad core system and 
see how it goes under benchmark...

Gordon

On Jun 17, 2009, at 8:16 AM, Steve Totaro wrote:
> Hi,
>
> Quick question to the real world.
>
> Approx what specs would I need on server to handle 95 ZAP or Dahdi - 
> > SIP gateway using G729 on the SIP to carrier side (nothing else,  
> just media conversion)?
>
> Does the latest Asterisk/DAHDI significantly improve these numbers  
> over say, Asterisk 1.2.X?
>
> Sure, there is plenty to read but nothing I could find quickly on my  
> exact needs that was clear and I want to be fairly sure before  
> ordering a server.
>
> Obviously load avg has something to do with it but CPU and mem seems  
> to be the biggest factors.
>
> -- 
> Thanks,
> Steve Totaro
> +18887771888 (Toll Free)
> +12409381212 (Cell)
> +12024369784 (Skype)

[Digium hat off, ITSP (previous employer) hat on.]

Not speaking for Digium on this one, but speaking from personal  
experience at another company.

We could get 100 G.729 channels in a 2x3ghz P4 machine with plenty of  
CPU room to spare, 4+ years ago, and that rule of thumb served us  
well.  This was for SIP (G.711<->G.729) but I can't imagine that DAHDI
or Asterisk takes significantly more or less horsepower for this task  
now for the base transcoding load.

JT

---
John Todd                       email:jtodd at digium.com
Digium, Inc. | Asterisk Open Source Community Director
445 Jan Davis Drive NW -  Huntsville AL 35806  -   USA
direct: +1-256-428-6083         http://www.digium.com/