Sorry for not describing the function of this BP clearly, this BP is not the same as your proposal.
Because the current bookkeeper does not have the ability to migrate data and can only perform data recovery, this BP mainly provides a data migration tool. When bookkeeper has data migration tool, the following scenarios can be solved: 1. The bookie nodes offline: As mentioned above, after bookkeeper has this data migration tool, the offline steps of bookie are only two steps, and the time-consuming is greatly reduced: a.Execute the data migration command: bin/bookkeeper shell replicasMigration --bookieIds bookie1,bookie2 --ledgerIds ALL --readOnly true b. When the data migration is completed, stop all bookie nodes to be offline; 2. Expand the bookie nodes to improve the reading speed of historical data: a. When the client consumes historical data a few days ago, it hopes to increase the reading speed of historical data by expanding the bookie node. b. When we expand the new bookie node to the cluster, the new node can only receive the read and write of new data, and cannot improve the reading speed of historical data. c. After the data migration tool of bookkeeper, we can migrate some historical data to the new node, let the new node provide some historical data reading, and improve the reading speed of historical data.
