[Asterisk-Users] Best CPU config for dual-Xeon?

[Damian Funnell]

Hi Tony, check out my recent post regarding our experiences with 
Hyperthreading and * with Zaptel cards.

We have a few machines in the wild that *do* run Hyperthreading but no 
Zaptel cards and these work absolutely fine.  My understanding is that 
the Hyperthreading problems are purely related to HW interrupts with Zaptel.

My advice would be to leave HT turned on and just turn it off if you 
have problems with it - something that takes are few seconds in the BIOS 
and doesn't require any software changes.  HT does provide significant 
performance improvements over non-HT... performance that could come in 
handy if your * server has a lot of calls in progress (and hence a lot 
of CODEC's to process).

Cheers,
Damian.

FFF Managed Technology Ltd
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P.O. 6368 Wellesley St
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Tony Mountifield wrote:

>I have some beefy dual-Xeon servers that I will be using for Asterisk
>VoIP applications (i.e. no Zaptel cards). Using 2.6.11-1.14_FC3smp
>as the kernel (Fedora Core 3), and currently with Asterisk STABLE.
>
>My question is concerning the CPU setup, as I've seen conflicting or
>out-of-date suggestions: given the above config, should I have
>hyper-threading turned on or off? Turned on appears like 4 CPUs,
>and turned off will, I assume, appear as 2 CPUs.
>
>It's not clear to me what the issues with HT are/were, and whether
>they only relate to the use of hardware, interrupts, etc. or what,
>so any advice would be much appreciated.
>
>Cheers
>Tony
>  
>