Increase checkpont details on tablespace

[diegosalvi]

FEATURE REQUEST

Currently timings on checkpoints are someway misleading and missing.
This is a log extract:

23-11-24-12-11-16       galletto checkpoint start ts1 at (1528,27505)
23-11-24-12-11-19       checkpoint done for table ts1.x1 (pin: false)
23-11-24-12-11-22       checkpoint done for table ts1.x2 (pin: false)
23-11-24-12-11-22       checkpoint done for table ts1.x3 (pin: false)
23-11-24-12-11-27       checkpoint done for table ts1.x4 (pin: false)
23-11-24-12-11-27       checkpoint done for table ts1.x5 (pin: false)
23-11-24-12-11-57       galletto checkpoint finish ts1 started ad (1528,27505), finished at (1528,27505), total time 46351 ms

The whole tablespace checkpoint needed a whopping 46seconds but really 30 seconds were spent beetween last table checkpoint and the end of the tablespace checkpoint.
In such phase there are at least 2 jobs to be done:
dropOldLedgers (done under tablespace write lock)
PostCheckpointAction.runs (outside tablespace write lock)
Which operation required so much time? We really don't know.

We should expand checkpoints log on tablespace to better understand where time is spent.