RFR: JDK-8323964: runtime/Thread/ThreadCountLimit.java fails intermittently on AIX [v2]

[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.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  adjust comment about MaxExpectedDataSegmentSize

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/17512/files
  - new: https://git.openjdk.org/jdk/pull/17512/files/47243ea9..de4dc68a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17512&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17512&range=00-01

  Stats: 8 lines in 1 file changed: 1 ins; 0 del; 7 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