feat(utils): add NodeJS profiler

[BioPhoton]

Related: #1197

This PR includes:

• adding NodeJSProfiler class
• implemented performanceObserver for NodeJSProfiler
• revamp PerformanceObserverSink - add getStatus for better testing, more robust and memory friendly buffer logic

Followup PRs:

• fix: add exit handler to profiler #1221

---

Note

Introduces a Node.js runtime profiler with buffered write-ahead logging and a redesigned performance observer.

• Adds NodejsProfiler (extends Profiler) with WAL sink integration, runtime enable/disable, state transitions, flush() and stats access; supports debug transition markers via CP_PROFILER_DEBUG
• Replaces PerformanceObserverSink internals with bounded queue, proactive flushing (flushThreshold), maxQueueSize, encode-failure debug marks, and getStats(); validates configuration and handles sink errors gracefully
• Expands WAL AppendableSink contract to include isClosed, optional open/close, and recovery APIs; updates mocks to MockAppendableSink/MockTraceEventFileSink
• Adds comprehensive unit/integration tests and new profiler.md docs covering configuration, API, and Node.js usage
• Minor: default exitOnFatal/exitOnSignal set to false in exit handlers

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---

☁️ Nx Cloud last updated this comment at 2026-01-27 00:43:57 UTC

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commit: 66523e3

[github-actions]

Code PushUp

🤨 Code PushUp report has both improvements and regressions – compared current commit 3cf7bef with previous commit e677d4f.

🕵️ See full comparison in Code PushUp portal 🔍

🏷️ Categories

🏷️ Category	⭐ Previous score	⭐ Current score	🔄 Score change
Documentation	🔴 46	🟡 53
Performance	🔴 36	🔴 35
Code coverage	🟢 93	🟢 93
Bug prevention	🟡 75	🟡 75
Axe Accessibility	🟡 88	🟡 88
Code style	🟢 100	🟢 100	–
Security	🔴 47	🔴 47	–
Updates	🟡 78	🟡 78	–
Type Safety	🟡 67	🟡 67	–
Miscellaneous	🟡 67	🟡 67	–
Accessibility	🟢 92	🟢 92	–
Best Practices	🟢 100	🟢 100	–
SEO	🟢 92	🟢 92	–

👍 1 group improved, 👎 2 groups regressed, 👍 8 audits improved, 👎 4 audits regressed, 15 audits changed without impacting score

🗃️ Groups

🔌 Plugin	🗃️ Group	⭐ Previous score	⭐ Current score	🔄 Score change
JSDocs coverage	Documentation coverage	🔴 46	🟡 53
Lighthouse	Performance	🔴 36	🔴 35
Code coverage	Code coverage metrics	🟢 93	🟢 93

31 other groups are unchanged.

🛡️ Audits

🔌 Plugin	🛡️ Audit	📏 Previous value	📏 Current value	🔄 Value change
JSDocs coverage	Properties coverage	🟥 41 undocumented properties	🟥 38 undocumented properties
JSDocs coverage	Methods coverage	🟨 15 undocumented methods	🟨 11 undocumented methods
JSDocs coverage	Classes coverage	🟨 6 undocumented classes	🟨 5 undocumented classes
Lighthouse	First Contentful Paint	🟥 3.1 s	🟥 3.4 s
Lighthouse	Speed Index	🟥 6.8 s	🟥 6.7 s
JSDocs coverage	Variables coverage	🟥 280 undocumented variables	🟥 273 undocumented variables
Lighthouse	Time to Interactive	🟥 13.3 s	🟥 13.7 s
JSDocs coverage	Types coverage	🟥 262 undocumented types	🟥 261 undocumented types
JSDocs coverage	Functions coverage	🟥 582 undocumented functions	🟥 582 undocumented functions
Code coverage	Line coverage	🟩 92.6 %	🟩 92.7 %
Code coverage	Branch coverage	🟨 89.2 %	🟨 89.2 %
Code coverage	Function coverage	🟩 94.3 %	🟩 94.3 %
Lighthouse	Avoids enormous network payloads	🟩 Total size was 2,091 KiB	🟩 Total size was 2,095 KiB
Lighthouse	Minimizes main-thread work	🟥 12.1 s	🟥 11.2 s
Lighthouse	Uses efficient cache policy on static assets	🟨 31 resources found	🟨 31 resources found
Lighthouse	Metrics	🟩 100%	🟩 100%
Lighthouse	JavaScript execution time	🟥 4.9 s	🟥 4.5 s
Lighthouse	Largest Contentful Paint	🟥 11.8 s	🟥 12.1 s
Lighthouse	Reduce unused CSS	🟥 Potential savings of 125 KiB	🟥 Potential savings of 125 KiB
Lighthouse	Remove duplicate modules in JavaScript bundles	🟥 Potential savings of 85 KiB	🟥 Potential savings of 88 KiB
Lighthouse	Server Backend Latencies	🟩 660 ms	🟩 790 ms
Lighthouse	Network Round Trip Times	🟩 0 ms	🟩 60 ms
Lighthouse	Total Blocking Time	🟥 1,810 ms	🟥 1,850 ms
Lighthouse	Initial server response time was short	🟩 Root document took 490 ms	🟩 Root document took 450 ms
Lighthouse	Max Potential First Input Delay	🟥 1,300 ms	🟥 1,290 ms
TypeScript	Semantic errors	🟥 25 errors	🟥 36 errors
Lighthouse	Reduce unused JavaScript	🟥 Potential savings of 226 KiB	🟥 Potential savings of 226 KiB

652 other audits are unchanged.

[github-actions]

Code PushUp

🤨 Code PushUp report has both improvements and regressions – compared current commit 3cf7bef with previous commit e677d4f.

💼 Project utils

🤨 Code PushUp report has both improvements and regressions.

🕵️ See full comparison in Code PushUp portal 🔍

🏷️ Category	⭐ Previous score	⭐ Current score	🔄 Score change
Documentation	🟡 51	🟡 60
Code coverage	🟢 95	🟢 95

4 other categories are unchanged.

👍 1 group improved, 👎 1 group regressed, 👍 7 audits improved, 👎 2 audits regressed

🗃️ Groups

🔌 Plugin	🗃️ Group	⭐ Previous score	⭐ Current score	🔄 Score change
JSDocs coverage	Documentation coverage	🟡 51	🟡 60
Code coverage	Code coverage metrics	🟢 95	🟢 95

13 other groups are unchanged.

🛡️ Audits

🔌 Plugin	🛡️ Audit	📏 Previous value	📏 Current value	🔄 Value change
JSDocs coverage	Properties coverage	🟥 38 undocumented properties	🟥 35 undocumented properties
JSDocs coverage	Methods coverage	🟨 15 undocumented methods	🟨 11 undocumented methods
JSDocs coverage	Classes coverage	🟨 3 undocumented classes	🟨 2 undocumented classes
JSDocs coverage	Variables coverage	🟥 57 undocumented variables	🟥 50 undocumented variables
JSDocs coverage	Types coverage	🟨 56 undocumented types	🟨 55 undocumented types
JSDocs coverage	Functions coverage	🟥 244 undocumented functions	🟥 244 undocumented functions
Code coverage	Branch coverage	🟩 92.2 %	🟩 92 %
Code coverage	Function coverage	🟩 96 %	🟩 95.9 %
Code coverage	Line coverage	🟩 97.9 %	🟩 97.9 %

435 other audits are unchanged.

---

13 other projects are unchanged.

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