Update stress test results for eventheader

[lalitb]

Changes

update stress test for eventheader crate. The stats don't differ whether tracepoint is enabled or disabled- as it only involves a single bit read in the kernel VFS, so haven't added separate test for it.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 54.3%. Comparing base (037f914) to head (aa23e27).
Report is 1 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #140   +/-   ##
=====================================
  Coverage   54.3%   54.3%           
=====================================
  Files         41      41           
  Lines       6227    6227           
=====================================
  Hits        3384    3384           
  Misses      2843    2843           

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[lalitb]

Attaching the flamegraph with single thread, and concurrent threads ( equal to number of logical processors):

concurrent enabled check:

Single thread enabled check:

The relevant part in the stack trace in flamegraph is the frequent context switching in concurrent enabled graph, which is missing in single thread check, Will investigate more.

However, the PR should be good to publish with these results. The investigation can follow further.

[cijothomas]

Thanks. I don't think we can invoke the check for each and every log, as it'll introduce contention to logging :( We can discuss some alternatives to avoid contention.

Also, we need to separately stress test if we see contention when actually exporting telemetry to user-events - it should be writing to per-cpu-buffer, so none is expected, but let us try and see if the assumptions hold true.