[jdk8u-dev] RFR: 8151460: Metaspace counters can have inconsistent values [v2]

[Thomas Stuefe]

> To reduce intermittent errors from TestPerfCountersAndMemoryPools, I'd like to backport "8151460: Metaspace counters can have inconsistent values".
> 
> This does not backport cleanly since JEP 280 [1] modified the test, and I won't backport that one of course. Therefore I also added the test-specific fix JEP 280 did (https://github.com/openjdk/jdk8u-dev/commit/24773b47512b522c9bfa346559a34138d900b77e).
> 
> Tests: I manually ran gc/metaspace jtreg tests on Linux x64 with fastdebug and release builds.
> 
> [1] https://bugs.openjdk.org/browse/JDK-8148483

Thomas Stuefe has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into TestPerfCountersAndMemoryPools
 - JDK-8151460: Metaspace counters can have inconsistent values
 - JEP 280 portion

-------------

Changes:
  - all: https://git.openjdk.org/jdk8u-dev/pull/301/files
  - new: https://git.openjdk.org/jdk8u-dev/pull/301/files/e66afb55..6ff57709

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=301&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=301&range=00-01

  Stats: 309 lines in 5 files changed: 252 ins; 24 del; 33 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/301.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/301/head:pull/301

PR: https://git.openjdk.org/jdk8u-dev/pull/301