Server load numbers

[NancyJ]

I have monitoring tools on my server and the load numbers are usually around 0.15 -1.5 ... but my questions is 0.15 what? What does the number mean? WHat is high?

[Noodles24]

If it's a linux server then 0.15 is 15%, 1 is 100%, if it's over 1 then you need more CPUs to handle the load, so if it's 2 then you'd need 2 CPUs to handle that load

[NancyJ]

We hve 2 CPUs so I wouldnt expect load to be higher than 2 then...
but this is our current readout:

CPU load averages: 2.01 (1 mins) , 4.17 (5 mins) , 3.96 (15 mins)

Now how can it get to over twice the number of CPUs we actually have? I've noticed on munin the CPU load graph goes up to 400%... how? The highest I've seen it is 25.5 if 1 is 100% 25.5 is 2550% CPU usage....

[Noodles24]

It means that the CPU is overloaded and a lot of instructions are probably queued. Linux/unix doesn't top out at 100% utilisation, so it gives you an idea on how overloaded the pc is.

Just remember if you have 2 CPUs, but they're both HT, it will look like 4 cpus.

[GJay]

No it doesn't. Don't spout nonsense.
The three numbers are the number of processes waiting for CPU time, now, the average for the past 5 minutes, and again for 15 minutes.

[NancyJ]

so if its 0.15 thats less than 1 waiting? If its 25 thats a lot waiting but makes a lot more sense than the server using 6.25x its max resources

[NancyJ]

Interestingly I just looked at the server and its running a high load and I cant tell why
Currently 85% free CPU but the load average is over 5? We're not under heavy traffic load, theres very little going on in the database, how is it so high?