asterisk users - Nov 2003 - processor limits of max concurrent users on a single system

Hello,

I am trying to figure out the maximum capacity of concurrent SIP users(SIP
to Zap T1 channels) on my asterisk system. I assume that the processor/RAM
is the weakest link in the chain in terms of capacity right now.

* see my configuration below

Right now with 18 concurrent users on SIP phones going out through Zaptel T1
channels I get an average of a 0.30 load average and 25% of my total RAM is
in use. One of the things I noticed is that the 1 second load average may
spike up to 0.90 and then go back down to 0.10 and the CPU idle will go from
100% to 0% every few seconds. I never have any iowait so I know nothing is
getting backlogged.

With my current equipment in this machine could I conclude that I can
reliably expect to have 60 cuncurrent SIP-to-Zap users on my system?


Configuration:
Asus 800MHz bus Motherboard
P4 2.8GHz with 800MHz bus
2GB DDR400 RAM
SCSI RAID 10 (4 drives mirrored and spanned)
one Digium T400 card
3 T1s plugged in
RedHat linux 9
no Xwindows or unnecessary services running


Any help would be appreciated,

MATT---

mattf wrote:
>Hello,
>
>I am trying to figure out the maximum capacity of concurrent SIP users(SIP
>to Zap T1 channels) on my asterisk system. I assume that the processor/RAM
>is the weakest link in the chain in terms of capacity right now.
>
>* see my configuration below
>
>Right now with 18 concurrent users on SIP phones going out through Zaptel T1
>channels I get an average of a 0.30 load average and 25% of my total RAM is
>in use. One of the things I noticed is that the 1 second load average may
>spike up to 0.90 and then go back down to 0.10 and the CPU idle will go from
>100% to 0% every few seconds. I never have any iowait so I know nothing is
>getting backlogged.
>
>With my current equipment in this machine could I conclude that I can
>reliably expect to have 60 cuncurrent SIP-to-Zap users on my system?
>
>
>Configuration:
>Asus 800MHz bus Motherboard
>P4 2.8GHz with 800MHz bus
>2GB DDR400 RAM
>SCSI RAID 10 (4 drives mirrored and spanned)
>one Digium T400 card
>3 T1s plugged in
>RedHat linux 9
>no Xwindows or unnecessary services running
>
>
>Any help would be appreciated,
>
>MATT---
>  
>
Are you using a HT processor and if so are you running the SMP kernel??

IIRC the load avereage is added together for each CPU so if a single CPU 
system had a max load average of 1.0 then a dual CPU system would have a 
max load avaerage of 2.0 and so on.. So if you are using HT and the SMP 
kernel then you should probably half your load average to get it back to 
a common base, and that would mean you have an actual load average of 
0.15.. Or am I completely wrong here!?!?

Later..