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My server's CPU shows high average LOAD but the %CPU usage is very low.

How can I investigate this issue and find the root cause?

Thank you. 

top - 07:40:21 up 339 days, 10:24,  1 user,  >>load average: 3.88, 4.30, 3.93<<
Tasks: 155 total,   2 running, 153 sleeping,   0 stopped,   0 zombie
Cpu(s): 95.4%us,  3.3%sy,  0.2%ni,  0.8%id,  0.0%wa,  0.0%hi,  0.3%si,  0.0%st
Mem:  15132964k total, 14578884k used,   554080k free,   190508k buffers
Swap:  8388604k total,  3092292k used,  5296312k free,  7686120k cached
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  • How many (logical) CPUs does the server have? If it’s just one, it’s 99.2% busy.
    – Daniel B
    Commented Jan 19, 2020 at 9:02
  • I understand at the that particular instance CPU was indeed busy. But the usage fell after it.But the average load stays above 3.
    – Chirag Rathod
    Commented Jan 19, 2020 at 14:36
  • Load is the number of running, runnable (plus, on Linux, I/O-waiting) processes. So you need to check those.
    – Daniel B
    Commented Jan 19, 2020 at 14:49

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It actually looks like your CPU usage is extremely high, with some user-mode process using 95.4% of the available CPU time! With only two tasks active (one of which will be top itself), it shouldn't be hard to tell which one is the problem. Look down the list of processes below the header of top to tell what the offending task is.

Figuring out what that task's problem is will be more complicated. It might be something simple and logical, like a compression algorithm working on a very large amount of data, a software rendering program trying to create a computationally expensive image, or similar. It might be due to an error in the program causing it to retry continuously. It might be a genuine infinite loop, with no way out except killing the process. Without knowing more about your machine, the process you're running, and possibly the environment in general, nobody here is going to be able to solve the problem for you.

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  • I understand at the that particular instance CPU was indeed busy. But the usage fell after it.But the average load stays above 3. Assuming the CPU is not an issue is there any other diagnosis that I can do for the high average load issue? Thank you!
    – Chirag Rathod
    Commented Jan 19, 2020 at 14:37

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