define paramter for reactor thread pool size

[thuvh]

No description provided.

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.60%. Comparing base (802240c) to head (0fcd96b).
Report is 28 commits behind head on main.

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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #325      +/-   ##
==========================================
+ Coverage   80.29%   81.60%   +1.30%     
==========================================
  Files           4        4              
  Lines         873      886      +13     
==========================================
+ Hits          701      723      +22     
+ Misses        172      163       -9     

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[thuvh]

@pryorda could you plz review this code?