fix: derive benchmark Throughput and Mean time per paragraph from ns/op

[nicobistolfi]

Summary

• .github/workflows/benchmark-profile.yml's Comment PR with results and Generate summary steps matched literal Throughput: and Mean time per paragraph: text that plain go test -bench -benchmem output never contains, so both fields always fell back to N/A (only ns/op matched and showed real data).
• Both steps now derive Throughput (1e9 / ns_per_op paragraphs/second) and a human-readable Mean time per paragraph directly from the ns/op value that was already being parsed successfully, falling back to N/A only when ns/op itself can't be parsed (avoiding NaN/Infinity).
• No Go code, benchmark functions, or profiling/artifact steps were changed — this is a CI reporting fix scoped entirely to the workflow file.

Closes #55

Test plan

• actionlint on the modified workflow file — no findings.
• Validated the workflow YAML parses correctly.
• Extracted the JS derivation logic (github-script step) into a standalone Node.js snippet and ran it against sample go test -bench output — confirmed real Throughput/Mean-time values are produced and are mathematically consistent with ns/op, and confirmed fallback to N/A (no NaN/Infinity) when ns/op can't be parsed.
• Extracted the bash derivation logic (Generate summary step) and ran it against the same sample output with awk — confirmed matching real values.
• go build ./... and go vet ./... — unaffected, pass.
• Verify on an actual PR run of benchmark-profile.yml that the posted comment and $GITHUB_STEP_SUMMARY show real, non-N/A values (requires this PR itself to trigger the workflow).

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[github-actions]

📊 Benchmark & Profile Results

Performance Summary

• Throughput: 2316.14 paragraphs/second
• Mean time per paragraph: 431.75 µs
• Nanoseconds per operation: 431753 ns/op

🔍 Interactive Profile Visualizations

View the interactive profile graphs directly in your browser:

📈 View CPU Profile →

• Download the artifact benchmark-profiles-47072f5ec6cafeba5bc316bdaa90b5637bd83654
• Open cpu_profile.html in your browser

💾 View Memory Profile →

• Download the artifact benchmark-profiles-47072f5ec6cafeba5bc316bdaa90b5637bd83654
• Open memory_profile.html in your browser

CPU Profile (Top 20)

File: deidentify.test
Build ID: f1b10fe871506f484c4d7c44a8c8012b97f0043d
Type: cpu
Time: 2026-08-11 17:47:16 UTC
Duration: 78.20s, Total samples = 192.06s (245.59%)
Showing nodes accounting for 185.11s, 96.38% of 192.06s total
Dropped 266 nodes (cum <= 0.96s)
Showing top 20 nodes out of 50
      flat  flat%   sum%        cum   cum%
    48.92s 25.47% 25.47%     57.82s 30.11%  regexp.(*machine).add
    30.39s 15.82% 41.29%     65.77s 34.24%  regexp.(*Regexp).tryBacktrack
       28s 14.58% 55.87%     72.82s 37.92%  regexp.(*machine).step
    22.55s 11.74% 67.61%     40.91s 21.30%  regexp/syntax.(*Inst).MatchRunePos
    18.27s  9.51% 77.13%     18.36s  9.56%  unicode.SimpleFold
     9.54s  4.97% 82.09%      9.55s  4.97%  regexp.(*bitState).shouldVisit (inline)
     4.90s  2.55% 84.65%      5.2...

Memory Profile (Top 20)

File: deidentify.test
Build ID: f1b10fe871506f484c4d7c44a8c8012b97f0043d
Type: alloc_space
Time: 2026-08-11 17:49:05 UTC
Showing nodes accounting for 1089.36MB, 99.13% of 1098.86MB total
Dropped 52 nodes (cum <= 5.49MB)
Showing top 20 nodes out of 36
      flat  flat%   sum%        cum   cum%
  347.09MB 31.59% 31.59%   791.27MB 72.01%  regexp.(*Regexp).replaceAll
  304.09MB 27.67% 59.26%  1095.36MB 99.68%  regexp.(*Regexp).ReplaceAllStringFunc
  244.29MB 22.23% 81.49%   244.29MB 22.23%  regexp.(*Regexp).get
  147.04MB 13.38% 94.87%   175.40MB 15.96%  regexp.(*Regexp).ReplaceAllStringFunc.func1
   27.50MB  2.50% 97.37%    27.50MB  2.50%  regexp.(*machine).alloc (inline)
   14.85MB  1.35% 98.73%    14.85MB  1.35%  regexp.(*bitState).reset
    2.50MB  0.23% 98.95%    28.51MB  2.59%  regexp.(*...

📥 All Artifacts Available

Download the complete profiling package from the workflow artifacts:

• 🌐 HTML Reports: cpu_profile.html, memory_profile.html (interactive visualizations)
• 📊 Graphs: CPU & Memory SVG/PNG files
• 📝 Text Reports: Full profiling data in text format
• 🎯 Focused Analysis: Deidentify-specific function profiling
• 📋 Raw Profiles: .prof files for custom analysis

Full Benchmark Output

goos: linux
goarch: amd64
pkg: github.com/aliengiraffe/deidentify
cpu: AMD EPYC 7763 64-Core Processor                
BenchmarkParagraphDeidentification-4           	   83028	    431753 ns/op	   10595 B/op	      48 allocs/op
BenchmarkParagraphDeidentificationParallel-4   	  182320	    197085 ns/op	    8691 B/op	      47 allocs/op
PASS
ok  	github.com/aliengiraffe/deidentify	78.222s
goos: linux
goarch: amd64
pkg: github.com/aliengiraffe/deidentify
cpu: AMD EPYC 7763 64-Core Processor                
BenchmarkParagraphDeidentification-4           	   27666	    434824 ns/op
BenchmarkParagraphDeidentificationParallel-4   	   60501	    203020 ns/op
PASS
ok  	github.com/aliengiraffe/deidentify	30.747s
goos: linux
goarch: amd64
pkg: github.com/aliengiraffe/deidentify
cpu: AMD EPYC 7763 64-Core Processor                
BenchmarkParagraphDeidentificationParallel-4   	   58497	    201363 ns/op
PASS
ok  	github.com/aliengiraffe/deidentify	13.894s

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Generated by Benchmark & Profile workflow run #31519210775 • Updated: Tue, 11 Aug 2026 17:49:34 GMT

[aotarola]

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