8351500: G1: NUMA migrations cause crashes in region allocation

[tstuefe]

This is not a clean backport. The effected G1Allocator and G1Collector methods have changed since JDK17.

So this backports reimplements the patch in a minimally invasive way while retaining as much similarity as possible with the original patch.

The gist of the patch is clear: instead of finding out the NUMA node index at every instance of G1Allocator::allocate_xxx, and then be subject to NUMA node migrations, we fix the NUMA node index once and use that one.

I tested this patch with my "FakeNUMA" addition (I plan to upstream that one at some point). This FakeNUMA mode mimics a lot of NUMA node migrations. I can verify that without this patch the JVM crashes quickly, with the patch it does not crash.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8351500 needs maintainer approval

Issue

• JDK-8351500: G1: NUMA migrations cause crashes in region allocation (Bug - P3 - Approved)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/3607/head:pull/3607
$ git checkout pull/3607

Update a local copy of the PR:
$ git checkout pull/3607
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/3607/head

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$ git pr checkout 3607

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https://git.openjdk.org/jdk17u-dev/pull/3607.diff

Using Webrev

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[bridgekeeper]

👋 Welcome back stuefe! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[tstuefe]

/approval request This is a solution for a quite hairy problem that hits customers on NUMA machines. It is rare, intermittent, and quite difficult to pinpoint. I therefore would appreciate it if I got approval for backporting.

Risk: lowish. The mechanism is quite clear, the patch, albeit unclean, simple in essence. I also took care to test its functioning well (see JBS description for details.)

[mlbridge]

Webrevs

• 00: Full (d863986c)

[openjdk]

@tstuefe
8351500: The approval request has been created successfully.

[tstuefe]

Ping @sjohanss - could I get a review for this?

[tstuefe]

Anyone?

[tstuefe]

Could I please have reviews? @jerboaa maybe or @gnu-andrew ?

[tstuefe]

@MDoerr or @MBaesken : would it be possible to send this through your JDK17 CI too, in case our tests missed something? Thanks!

[MBaesken]

Yes we can test it.