[asterisk-users] Hyperthreading and multicore

[Stelios Koroneos]

> Asterisk didn't benefit much from having HT enabled on a P4 
> with HT capability.
> 

There are several things that make a difference when optimizing for a
specific processor in order to take advantage of its features.
Gcc version used to build asterisk (and the system in general) and compile
flags can make a big difference
A lot of the "ready made" solutions use very generic optimization as they
are trying to be compatible with a wide range of cpu core's and
architectures.
This has the advantage of having a single binary image to distribute but you
pay for it in terms of performance.
In most cases the performance penalty is not noticable in small/home
installations but you start to notice it when you push the system to its
"resource" limit
(i.e cpu, memory,pci bus access etc) either because you handle a lot of
calls or your system is "resourse limited" i.e embedded boards.
So in general if you need to get the maximum performance out of a system,
make sure you build asterisk tuned for that system and not a "generic"
build.
Running code with 486 instruction set, with command scheduling for pentium
its not going to give you max performance regardless of the fact that your
cpu/core supports HT or not.



Stelios S. Koroneos

Digital OPSiS - Embedded Intelligence
http://www.digital-opsis.com