In the log the "Preserve CM Refs" category is far away from the "Parallel Preserve CM Refs" category, while they should be one after another.

 [0.251s][info ][gc,phases ] GC(0) Other: 1.4ms
[0.251s][debug][gc,phases ] GC(0) Choose CSet: 0.0ms
[0.251s][debug][gc,phases ] GC(0) Preserve CM Refs: 0.2ms
[0.251s][debug][gc,phases ] GC(0) Reference Processing: 0.2ms
[0.251s][debug][gc,phases ] GC(0) Reference Enqueuing: 0.0ms
[0.251s][debug][gc,phases ] GC(0) Redirty Cards: 0.1ms
[0.251s][trace][gc,phases ] GC(0) Parallel Redirty (ms): Min: 0.0, Avg: 0.0, Max: 0.0, Diff: 0.0, Sum: 0.2
[0.251s][trace][gc,phases,task ] GC(0) 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
[0.251s][trace][gc,phases ] GC(0) Redirtied Cards: Min: 0, Avg: 0.0, Max: 0, Diff: 0, Sum: 0
[0.251s][trace][gc,phases,task ] GC(0) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
[0.251s][trace][gc,phases ] GC(0) Parallel Preserve CM Refs (ms): Min: 0.0, Avg: 0.1, Max: 0.2, Diff: 0.2, Sum: 2.8
[0.251s][trace][gc,phases,task ] GC(0) 0.1 0.1 0.1 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1