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A comment on CPU Utilization is Wrong.

Re:CPU Utilization is Wrong by xroche on Wednesday May 10, 2017 @01:09AM (#14306041)
> You can figure out what %CPU really means by using additional metrics, including instructions per cycle (IPC)

Correct me if I am wrong, but this won't work for spinlocks in busy loops: you do have a lot of instructions being executed, but the whole point of the loop is to wait for the cache to synchronize, and as such, this should be taken as "stalled".

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Re:CPU Utilization is Wrong by IIIIIIIIIIII on Wednesday May 10, 2017 @02:35AM (#14306305)
Which is mentioned in the article (which few people fully read of course)!

See under "Other reasons CPU Utilization is misleading"

> Spin locks: the CPU is utilized, and has high IPC, but the app is not making logical forward progress.

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