RFR: JDK-8323964: runtime/Thread/ThreadCountLimit.java fails intermittently on AIX

[Matthias Baesken]

Every 1-2 months we run into into such kind of failures on AIX:


[2.498s][warning][os,thread] Failed to start thread "Unknown thread" - pthread_create failed (11=EAGAIN) for attributes: stacksize: 2112k, guardsize: 0k, detached.
[2.498s][warning][os,thread] Number of threads approx. running in the VM: 4223
[2.498s][warning][os,thread] Checking JVM parameter MaxExpectedDataSegmentSize (currently 8388608k) might be helpful
[2.498s][warning][os,thread] Failed to start the native thread for java.lang.Thread "Thread-4213"

[error occurred during error reporting (), id 0xe0000000, Internal Error (/workspace/openjdk-jdk-dev-aix_ppc64-dbg/jdk/src/hotspot/os/aix/os_aix.cpp:2971)]
#
# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (malloc) failed to allocate 56 bytes. Error detail: AllocateHeap
[thread 3856 also had an error]
# An error report file with more information is saved as:
# /tmp/hs_err_pid13959464.log
[thread 76331 also had an error]


Seems the MaxExpectedDataSegmentSize (Maximum expected size of the data segment, AIX specific flag)
settings in in some cases too low for the test.
We experienced this a few times in scenarios where a lot of threads are created (and even warn about this, see os_aix.cpp).
So we should better run with a higher than default value of MaxExpectedDataSegmentSize for this test.

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Commit messages:
 - JDK-8323964

Changes: https://git.openjdk.org/jdk/pull/17512/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17512&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8323964
  Stats: 10 lines in 1 file changed: 9 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/17512.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17512/head:pull/17512

PR: https://git.openjdk.org/jdk/pull/17512