Send a correct size hint to the sidecar trace flusher

[bwoebi]

Also, initial stack size is a low number. Also the wrong number, generally. Instead, we'll flush the traces in the sidecar when a significant percentage of the max payload size is reached.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 77.84%. Comparing base (44945bb) to head (1485476).

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2686      +/-   ##
============================================
+ Coverage     77.79%   77.84%   +0.04%     
  Complexity     2223     2223              
============================================
  Files           226      226              
  Lines         26357    26357              
  Branches        988      988              
============================================
+ Hits          20505    20517      +12     
+ Misses         5326     5314      -12     
  Partials        526      526              

Flag	Coverage Δ
appsec-extension	69.13% <ø> (ø)
tracer-extension	78.66% <50.00%> (ø)
tracer-php	80.46% <ø> (+0.13%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
ext/sidecar.c	88.18% <100.00%> (ø)
ext/auto_flush.c	56.17% <0.00%> (ø)

... and 1 file with indirect coverage changes

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[pr-commenter]

Benchmarks

Benchmark execution time: 2024-05-31 23:52:54

Comparing candidate commit 1485476 in PR branch bob/fix-trace-flush-size with baseline commit 44945bb in branch master.

Found 6 performance improvements and 0 performance regressions! Performance is the same for 172 metrics, 0 unstable metrics.

scenario:EmptyFileBench/benchEmptyFileOverhead

• 🟩 execution_time [-607.258µs; -429.842µs] or [-12.930%; -9.153%]

scenario:EmptyFileBench/benchEmptyFileOverhead-opcache

• 🟩 execution_time [-587.636µs; -459.084µs] or [-12.144%; -9.488%]

scenario:LaravelBench/benchLaravelOverhead

• 🟩 execution_time [-564.463µs; -467.457µs] or [-11.499%; -9.523%]

scenario:LaravelBench/benchLaravelOverhead-opcache

• 🟩 execution_time [-584.255µs; -485.725µs] or [-11.608%; -9.651%]

scenario:SymfonyBench/benchSymfonyOverhead

• 🟩 execution_time [-560.372µs; -508.748µs] or [-5.444%; -4.942%]

scenario:SymfonyBench/benchSymfonyOverhead-opcache

• 🟩 execution_time [-485.129µs; -421.691µs] or [-4.661%; -4.052%]