Implementation something similar to HDFS's NameNode#startTrashEmptier in OzoneManager to enable automatic trash clean up.
1. Ozone doesn't support efficient directory renaming (not until HDDS-2939 is fully merged).
- Possible solution: Override TrashPolicyDefault by setting fs.trash.classname in core-site.xml. So we can move files under /.Trash/<timestamp_of_delete>/ instead of /.Trash/Current/ to avoid folder renaming during checkpointing.
- But this fs.trash.classname might affect ALL other FileSystems if configured in core-site.xml.
- If there a way to only apply the config to o3fs and ofs.
In the design doc, #4 is the one we are looking at. But that approach is blocked by HDDS-3620 if we need an elegant way to implement batch rename on server side.