[Asterisk-Users] CPU load (was: dimensioning: Where is the CPU vs Asterisk load table)

[Simone Cittadini]

Erick Perez ha scritto:

>
>-And the most important I read was: Keep load under 5 in single CPUs
>and 10 in dual CPUs (didn't mention dual cores in the article).
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That seemed to me a lot, so i googled around a little trying to 
understand the true meaning of those numbers :
I'll sum up here what I've found, sparing you the formulae (look for 
"linux load average" "neil gunther")
First of all the sampling of cpu load gives more weight to recent 
samples, so is better to look at the third value, average in the last 15 
minutes, without being scared by high "punctual" values. Following "what 
the gurus says" the value should be kept below 3, or below the number of 
cpus, given what we are measuring (the number of process ready and 
waiting to be executed), those values means to me "a rule of thumb" and 
"make no one wait to do his job". It's not a lot of meaning, is it ?
What I suppose we want to say is "when I start hearing the calls bad ?", 
like gamers don't care about FPS but want to know "which graphic card I 
have to buy to frag aliens smoothly ?". I'm not a C programmer so I 
don't know asterisk internals, what I'll say now maybe is totally 
nonsense, I leave the sensate replies to the community.
If I have an asterisk process waiting, is sensate to state that if it 
waits too long, when his turn comes he'll drop the packets as the 
timestamp on them is too old and sound quality will start decreasing ?
If this is the case, isn't the important measure not "how many are 
waiting" but "how long are they waiting" ? Since the upper bound to load 
should be "low enough so they don't have to drop" .

(as a fast reply I can say that I made some calls while my dual 3.0 Ghz 
was under load 5, and they sounded good, alaw no transcoding)