[asterisk-biz] Big PBX

[Alistair Cunningham]

Steve Totaro wrote:
>> Trixter,
>>
>> I can't give you concurrent call figures for these systems as we 
>> haven't got permission from our customers to share this information, 
>> though you can safely assume many more than 200 total concurrent calls.
>>
>> The 200 concurrent calls in my previous email is per Asterisk machine 
>> (with all but the smallest Enswitch systems having more than one 
>> Asterisk machine), and is general advice to new customers. The exact 
>> figure will of course depend on hardware, codecs, average call length, 
>> etc.
>>
>> Alistair Cunningham
>> +1 888 468 3111
>> +44 20 799 39 799
>> sip:acunningham at integrics.com
>> http://integrics.com/
>>
> How does average call length have anything to do with number of 
> concurrent calls?

Steve,

Enswitch does a set of database queries at the start and end of each 
call to:

1. Route the call, including things like caller and time of day routing.
2. Decide whether the customer has enough credit, and how long to let 
the call run before cutting it off.
3. Update the table of active calls.
4. Write CDRs.
5. Bill the call and update the customer's and any parent resellers' 
and/or affiliates' balances.
6. Minor tasks such as updating busy lamps, etc.

If calls are short, these tasks take up a larger fraction of the 
processor time, leaving less processor time available for mid-call tasks 
such as codec translation.