8273372: Remove scavenge trace message in psPromotionManager

[albertnetymk]

Simple change of moving ResourceMark closer to where it is actually required.

Test: tier1-6

---

Progress

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Issue

• JDK-8273372: Remove scavenge trace message in psPromotionManager

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Leo Korinth (@lkorinth - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (ec25f9e9)
• 00: Full (c6c9335e)

[tschatzl]

I did some looking whether there are similar places to look out for, but found nothing.

Also, I would not be opposed to completely remove that trace message: while trace messages may slow down the garbage collection significantly, this message probably does so way too much to be useful for any kind of output; I understand that this message is enabled in development builds only too, but the other collectors do not have similar messages anyway. Additionally, even when debugging it helps much more to have some a bit more targeted log message; this is kind of a last resort to dump everything. At that point during debugging adding just another log message is probably not too much of a bother (as you probably have exhausted all other options and littered the code with such messages already. I "know" because I just went through that exercise with another issue in g1, and that single one message wouldn't have helped me in any significant way).

So long story short, if you want to remove that message fine with me, but it might be a good idea to consider other opinions too.

So lgtm.

[openjdk]

@albertnetymk This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8273372: Remove scavenge trace message in psPromotionManager

Reviewed-by: tschatzl, lkorinth

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 151 new commits pushed to the master branch:

• 241ac89: 8273606: Zero: SPARC64 build fails with si_band type mismatch
• 181292d: 8273801: Handle VMTYPE for "core" VM variant
• 09ecb11: 8273806: compiler/cpuflags/TestSSE4Disabled.java should test for CPU feature explicitly
• 99cfc16: 8273805: gc/g1/TestGCLogMessages.java test should handle non-JFR configs
• 1c5de8b: 8273807: Zero: Drop incorrect test block from compiler/startup/NumCompilerThreadsCheck.java
• 46af82e: 8273804: Platform.isTieredSupported should handle the no-compiler case
• 2d13fb2: 8273803: Zero: Handle "zero" variant in CommandLineOptionTest.java
• d4546b6: 8273526: Extend the OSContainer API pids controller with pids.current
• 74ffe12: 8273575: memory leak in appendBootClassPath(), paths must be deallocated
• cbffecc: 8273832: gc/shenandoah/TestJcmdHeapDump.java does not have a @requires vm.gc.shenandoah
• ... and 141 more: https://git.openjdk.java.net/jdk/compare/23fa0dcff062803d249c863b90a00744e3477656...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[albertnetymk]

Log tag, scavenge, only has develop_trace level logs. If they are rarely useful, they should be removed. (I used scavenge) to see locate them.)

[tschatzl]

Looking at it a bit more, probably all of these gc, scavenge log messages should get the same treatment with the local ResourceMark. They will otherwise eat tons of memory as every string for every object will be newly allocated in the resource area.

That does not preclude just removing these, but my opinion stands: at the point when you need those, you'll have likely exhausted lots of other avenues already. However maybe this is just my feeling because G1 does not have these, and there you'll need to add messages always. An alternative could be to add similar messages to G1?

It would be good if somebody else could give his opinion.

[lkorinth]

While the change looks good, I agree with Thomas that it is better to remove the trace altogether. Also, in general it is not always better to move the ResourceMark closer to the allocation. I think you should rename the enhancement to a name that betters describe the new code, and removing the trace (and ResourceMark) is the best way forward.

[albertnetymk]

Removed those trace messages as suggested, because the signal-to-noise ratio is too low in them.

[lkorinth]

Looks good to me!

[tschatzl]

Ship it.

[albertnetymk]

Thanks for the review.

/integrate

[openjdk]

Going to push as commit 14dc517.
Since your change was applied there have been 151 commits pushed to the master branch:

• 241ac89: 8273606: Zero: SPARC64 build fails with si_band type mismatch
• 181292d: 8273801: Handle VMTYPE for "core" VM variant
• 09ecb11: 8273806: compiler/cpuflags/TestSSE4Disabled.java should test for CPU feature explicitly
• 99cfc16: 8273805: gc/g1/TestGCLogMessages.java test should handle non-JFR configs
• 1c5de8b: 8273807: Zero: Drop incorrect test block from compiler/startup/NumCompilerThreadsCheck.java
• 46af82e: 8273804: Platform.isTieredSupported should handle the no-compiler case
• 2d13fb2: 8273803: Zero: Handle "zero" variant in CommandLineOptionTest.java
• d4546b6: 8273526: Extend the OSContainer API pids controller with pids.current
• 74ffe12: 8273575: memory leak in appendBootClassPath(), paths must be deallocated
• cbffecc: 8273832: gc/shenandoah/TestJcmdHeapDump.java does not have a @requires vm.gc.shenandoah
• ... and 141 more: https://git.openjdk.java.net/jdk/compare/23fa0dcff062803d249c863b90a00744e3477656...master

Your commit was automatically rebased without conflicts.

[openjdk]

@albertnetymk Pushed as commit 14dc517.

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