Deduplicate events happening in multiple threads simultaneously

[romtsn]

📜 Description

Introduce new DeduplicateMultithreadedEventProcessor which keeps an in-memory cache of crashed events in a form of map/dict (crash type - thread id). If a crash type has already been processed once and coming in again from a different thread, the processor will drop the event.

This can be the case for OutOfMemoryError, when multiple threads are trying to allocate new memory and therefore crashing within the same millisecond from multiple threads. When this happens, the events are almost equal, except the thread id and timestamp. We've seen this for one of our customers and also were somewhat able to reproduce it locally.

💡 Motivation and Context

Closes #2827

💚 How did you test it?

Manually and automated

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[romtsn]

The change is needed because otherwise the other crashing threads will not hold a lock anymore and will crash the app immediately, not giving a chance to persist the crash that was the first one (the one which we're going to deduplicate).

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	391.37 ms	407.69 ms	16.32 ms
Size	1.72 MiB	2.29 MiB	575.23 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
496bdfd	272.86 ms	407.33 ms	134.48 ms
f274c79	313.96 ms	355.96 ms	42.00 ms
d0c08e7	310.28 ms	350.68 ms	40.40 ms
caf50ec	302.36 ms	325.25 ms	22.89 ms
8820c5c	330.60 ms	416.86 ms	86.26 ms
adf8fe3	300.49 ms	357.36 ms	56.87 ms
9246ed4	281.79 ms	352.08 ms	70.29 ms
f274c79	334.86 ms	348.54 ms	13.68 ms
dc67004	273.86 ms	346.37 ms	72.51 ms
3baa73f	267.45 ms	388.30 ms	120.85 ms

App size

Revision	Plain	With Sentry	Diff
496bdfd	1.72 MiB	2.28 MiB	571.82 KiB
f274c79	1.72 MiB	2.29 MiB	575.01 KiB
d0c08e7	1.72 MiB	2.29 MiB	574.68 KiB
caf50ec	1.72 MiB	2.29 MiB	575.24 KiB
8820c5c	1.72 MiB	2.28 MiB	571.82 KiB
adf8fe3	1.72 MiB	2.29 MiB	575.24 KiB
9246ed4	1.72 MiB	2.28 MiB	572.22 KiB
f274c79	1.72 MiB	2.29 MiB	575.01 KiB
dc67004	1.72 MiB	2.28 MiB	573.45 KiB
3baa73f	1.72 MiB	2.29 MiB	575.52 KiB

Previous results on branch: rz/fix/dedupe-ooms

Startup times

Revision	Plain	With Sentry	Diff
c97d70e	305.20 ms	386.12 ms	80.92 ms
fb09880	315.44 ms	372.08 ms	56.64 ms
6772551	274.81 ms	327.41 ms	52.60 ms

App size

Revision	Plain	With Sentry	Diff
c97d70e	1.72 MiB	2.29 MiB	575.82 KiB
fb09880	1.72 MiB	2.29 MiB	575.23 KiB
6772551	1.72 MiB	2.29 MiB	575.82 KiB

[markushi]

Nice one, LGTM!

[codecov]

Codecov Report

Patch coverage: 94.59% and project coverage change: +0.05 🎉

Comparison is base (288f538) 81.31% compared to head (9f0d9d5) 81.37%.

❗ Current head 9f0d9d5 differs from pull request most recent head 9bc6ed1. Consider uploading reports for the commit 9bc6ed1 to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2845      +/-   ##
============================================
+ Coverage     81.31%   81.37%   +0.05%     
- Complexity     4619     4633      +14     
============================================
  Files           352      354       +2     
  Lines         17030    17064      +34     
  Branches       2302     2307       +5     
============================================
+ Hits          13848    13885      +37     
+ Misses         2232     2229       -3     
  Partials        950      950              

Impacted Files	Coverage Δ
sentry/src/main/java/io/sentry/TypeCheckHint.java	0.00% <ø> (ø)
...sentry/DeduplicateMultithreadedEventProcessor.java	92.30% <92.30%> (ø)
sentry/src/main/java/io/sentry/SentryEvent.java	89.43% <100.00%> (+0.07%)	⬆️
...io/sentry/UncaughtExceptionHandlerIntegration.java	90.41% <100.00%> (+7.31%)	⬆️
...src/main/java/io/sentry/hints/EventDropReason.java	100.00% <100.00%> (ø)
sentry/src/main/java/io/sentry/util/HintUtils.java	80.00% <100.00%> (+1.87%)	⬆️

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