RFR (XXS): 8200365: TestOptionsWithRanges.java of '-XX:TLABWasteTargetPercent=100' fails intermittently

Thomas Schatzl thomas.schatzl at oracle.com
Thu Aug 9 10:34:03 UTC 2018


Hi,

  can I have reviews for this tiny fix that fixes startup issues with
serial, parallel and CMS collectors?

The reason is that high values of TLABWasteTargetPercent (>=26) cause
TLABs getting to large during startup with default ergonomics, causing
a GC when a second Java thread wants to allocate its TLAB.
However at that time we do not support GCs, and so the VM forcibly
fails.

The fix is to increase the number of refills per thread for the initial
TLAB size calculation only.

CR:
https://bugs.openjdk.java.net/browse/JDK-8200365
Webrev:
http://cr.openjdk.java.net/~tschatzl/8200365/webrev/
Testing:
Running failing test with serial/parallel/cms 400 times each without
failure.

Thanks,
  Thomas



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