RFR: 8335625: Update Javadoc for GetCpuLoad

[Kevin Walls]

On Mon, 12 Aug 2024 12:33:04 GMT, Joakim Nordström <jnordstrom at openjdk.org> wrote:

> Can I get a review of this documentation update to clarify the usage of GetCpuLoad (and inherently deprecated GetSystemCpuLoad) and GetProcessCpuLoad.
> 
> Calling either of these methods in quick succession can lead to unrepresentative results due to too few data points.
> 
> This behavior is easy to reproduce on at least Linux (Windows implementation enforces a 500 ticks duration); when calling GetCpuLoad repeatedly CPU load values of either 0, 0.5, or 1 will be returned.
> 
> double cpuLoad1 = getCpuLoad();
> double cpuLoad2 = getCpuLoad();   // not enough ticks has passed to give representative values
> 
> Worth noting is that this holds true even if getSystemCpuLoad() is called. 
> 
> double cpuLoad1 = getCpuLoad();
> double cpuLoad2 = getSystemCpuLoad();   // not enough ticks has passed to give representative values, since getSystemCpuLoad effectively calls getCpuLoad.

This is a helpful clarifying comment in the docs to avoid some confusion that's been seen with these methods.

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Marked as reviewed by kevinw (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/20546#pullrequestreview-2250453882