RFR: 8297570: jdk/jfr/threading/TestDeepVirtualStackTrace.java fails with -XX:-UseTLAB

[Markus Grönlund]

On Thu, 24 Nov 2022 11:32:29 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> This is the only test in `jdk_loom` that fails without `-XX:-UseTLAB`. The test specifically looks for `ObjectAllocationOutsideTLAB` event, and there are lots of those events with `-XX:-UseTLAB`. We can fix the test to look for the event we actually want.
> 
> This depends on [JDK-8297491](https://bugs.openjdk.org/browse/JDK-8297491) that fixed Loom code to actually disable TLABs.
> 
> Additional testing:
>  - [x] Linux x86_64 fastdebug, affected test with `-XX:+UseTLAB` and `-XX:-UseTLAB`
>  - [x] Linux x86_64 fastdebug, `jdk_loom` with `{Serial, Parallel, G1, Shenandoah, Z} x {+UseTLAB, -UseTLAB}`

test/jdk/jdk/jfr/threading/TestDeepVirtualStackTrace.java line 109:

> 107:                 System.out.println(event);
> 108:                 RecordedStackTrace stackTrace = event.getStackTrace();
> 109:                 if (stackTrace == null) {

This is interesting. Did you see events that did not have a stacktrace associated? jdk.ObjectAllocationOutsideTLAB?

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

PR: https://git.openjdk.org/jdk/pull/11352