Found with OpenDJ 3.0.0 rev 4d9a927848fc09827974e85c7736d56aad46c792
Installing 2 DS RS with PDB, enabling replication between each DS-RS, then between the 2 DS.
We then run modrate targeting each DS, during 3 days, setting the purge delay to 3days/10.
Changelog file is growing (after 1 day and a half, around 300G), the changenumberindex directory contains an empty head.log file.
It then fills up the disk.