[#2670]use java system api to retrieve CPU usage

[liubao68]

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (76854ff) 74.14% compared to head (1967531) 74.17%.
Report is 1 commits behind head on 2.8.x.

❗ Current head 1967531 differs from pull request most recent head 1fe9c1a. Consider uploading reports for the commit 1fe9c1a to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##              2.8.x    #4098      +/-   ##
============================================
+ Coverage     74.14%   74.17%   +0.03%     
  Complexity      707      707              
============================================
  Files          1598     1594       -4     
  Lines         40252    40142     -110     
  Branches       3675     3655      -20     
============================================
- Hits          29844    29775      -69     
+ Misses         8917     8885      -32     
+ Partials       1491     1482       -9     

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