RFR: 8318757: 8318757 VM_ThreadDump asserts in interleaved ObjectMonitor::deflate_monitor [v2]

[Stefan Karlsson]

On Mon, 6 Nov 2023 12:49:06 GMT, Axel Boldt-Christmas <aboldtch at openjdk.org> wrote:

>> Stefan Karlsson has updated the pull request incrementally with three additional commits since the last revision:
>> 
>>  - Move ConcurrentDeflation.java out of tier1
>>  - Update comments
>>  - Use a named constant
>
> src/hotspot/share/runtime/synchronizer.hpp line 135:
> 
>> 133: 
>> 134:   // Iterate owned ObjectMonitors
>> 135:   static void monitors_iterate(MonitorClosure* closure);
> 
> Should the preconditions described in the implementation be documented in the header as well. Or at least have a note along the lines of `See ObjectSynchronizer::monitors_iterate_filtered for details on the contract for using this.`

I've unified and updated the comments both files.

> src/hotspot/share/runtime/vmOperations.cpp line 398:
> 
>> 396:     // to take more then a few milliseconds.
>> 397:     size_t monitors_count = ObjectSynchronizer::in_use_list_count();
>> 398:     if (monitors_count > 100000) {
> 
> Maybe use a named constant.

Done

> test/hotspot/jtreg/runtime/Monitor/ConcurrentDeflation.java line 41:
> 
>> 39: 
>> 40: public class ConcurrentDeflation {
>> 41:     public static final int TOTAL_RUN_TIME = 10 * 1000;
> 
> Given that this test always runs for at least 10 seconds, maybe it should be excluded from tier1. See `test/hotspot/jtreg/TEST.groups`.
> 
> Unsure what the praxis is here.

Done

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

PR Review Comment: https://git.openjdk.org/jdk/pull/16519#discussion_r1383308219
PR Review Comment: https://git.openjdk.org/jdk/pull/16519#discussion_r1383308671
PR Review Comment: https://git.openjdk.org/jdk/pull/16519#discussion_r1383307219