[asterisk-users] RE: Scaling Asterisk: Dual-Core CPUs not yielding gains at high call volumes

[Matthew J. Roth]

JR Richardson wrote:
> The Dual-Core system you are working with must have cost a bundle, several
> thousand.  My approach has been to stick with single cpu, single core
> servers and add more servers to the cluster, versus building bigger, faster
> Proc servers. With sub $1000 servers, I can achieve 150-200 calls per
> server, cluster several servers together and for the same price as a quad
> proc dual-core server have 700-1000 call capacity.
>
> Now, with that said, a cluster becomes harder to build and operate than a 1
> server Asterisk implementation and does not work well in some environments,
> such as with large call queues.  But when you are talking straight call
> capacity, multiple servers will usually dominate singe servers in relation
> to cost.
At the start of our Asterisk project, scaling vertically seemed like the 
simpler approach and to a certain extent it is necessary because of our 
call queues.  Now that it seems like we've pushed this approach as far 
as it will go, my eagerness to study and implement Asterisk clusters is 
growing.  I know that horizontal scaling will have its own set of 
problems, but at this point I think they will be more manageable than 
what we're currently dealing with.

Could you please give me a rough overview of your clustering 
architecture?  I don't need too many details, but a list of the 
technologies/programs you are using would be a great basis for my 
research.  I currently planning to look into SER and DUNDi, and another 
poster suggested looking at OpenSSI. 
> Nice discussion, and thanks for posting your benchmark results and feedback.
>   
You're welcome.  I'll post some large scale numbers off of our 
production server soon.  I'm also going to start looking at SIPp, which 
may give me a way to gather large scale statistics in a more controlled 
environment.

Thank you for your responses,

Matthew Roth
InterMedia Marketing Solutions
Software Engineer and Systems Developer