
Linux console based monitoring tools report misleading utilization - ktsaou
https://github.com/firehol/netdata/wiki/Linux-console-based-monitoring-tools-report-misleading-utilization
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dozzie
Oh, no, not quite. It's just you who doesn't understand the OS, that's all.
It's sort of funny, given that you post it under _monitoring tool_ umbrella.

> Let's see an example. Execute this in a shell:

> while [ 1 ]; do ls -l /tmp >/dev/null; done

[...] > As we will see below, none of the console performance monitoring tools
can report that this command is using 100% CPU.

It's not _a command_. It's a _shell loop_ , meaning it's _many commands_ ,
executed one after another.

> They do report of course that the CPU is busy, but they fail to identify the
> process that consumes so much CPU.

Actually, they tell that the busywork is in _kernel_ space. Which usually
means heavy syscall workload. What quite often means some idiot runs plenty of
fork()+exec() in a tight loop.

