8370242: JFR: Clear event reference eagerly when using EventStream

[egahlin]

Could I have review of a change that reduce the live set when using event streaming?

The EventDirectoryStream and EventFileStream classes may hold on to events longer than needed. If a burst of events occurs, the sorted cache is filled, but if fewer events are emitted later, old events still remain in the cache array. They should be cleared after they have been dispatched.

This is effectively a memory leak, although it does not grow over time.

Testing: jdk/jdk/jfr

Thanks
Erik

---

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Issue

• JDK-8370242: JFR: Clear event reference eagerly when using EventStream (Bug - P3)

Reviewers

• Markus Grönlund (@mgronlun - Reviewer)

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8370242: JFR: Clear event reference eagerly when using EventStream

Reviewed-by: mgronlun

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At the time when this comment was updated there had been 22 new commits pushed to the master branch:

• 9a88d7f: 8369211: AArch64: Devirtualize class RelocActions
• b77b910: 8369349: Add missing CPE headers
• 0529a58: 8370326: Parallel: Remove unused ParCompactionManager::push
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Webrevs

• 00: Full (8be2e671)

[mgronlun]

Looks good.

[egahlin]

/integrate

[openjdk]

Going to push as commit 65b3239.
Since your change was applied there have been 43 commits pushed to the master branch:

• cbbb0a8: 8367976: Validate and clamp jdk.httpclient.bufsize
• 763d425: 8368781: PerfMemory - make issues more transparent
• 6010457: 8370378: Some compiler tests inadvertently exclude particular platforms
• ... and 40 more: https://git.openjdk.org/jdk/compare/dc6858f336a9acaac26d302fdc462ac1ed5c94ba...master

Your commit was automatically rebased without conflicts.

[openjdk]

@egahlin Pushed as commit 65b3239.

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