CPU Load – Understanding Top and Load Average

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I'm observing a high load average on a certain machine (about 9) in all three load fields. I understand load as the number of processes in state "run" / currently desiring CPU time. Am I correct at reasoning that if N processes are running on my machine this cannot produce a load greater than N?

Also, does the load count in respect to processes or threads? In other words, can a multithreaded process produce a load greater than 1?

Best Answer

Load average is usually described as "average length of run queue". So few CPU-consuming processes or threads can raise LA above 1. There is no problem if LA is less than total number of CPU cores. But if it gets higher than number of CPUs, this means some threads/processes will stay in queue, ready to run, but waiting for free CPU.

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