Comment 5 for bug 1595394

The less painful is very complex and this feature is what we need(but now, it will be a long time with a lot of work), this maybe xtrabackup issues, someday we want to support MyRocks in xtrabackup, how we do it?
To your drawbacks:
1) The checkpoint which after re-enabling is a normal checkpoint as we do periodically.The difference is it needs to remove more redo-logs, and the CP(1) is very fast.
2) under FTWRL(it's LOCK TABLES FOR BACKUP in PS5.7), there are just a few TokuDB redo-logs to copy(CP(1)), it would be better if we copying them in parallel.
3) Y
4) N, tokudb_checkpoint_lock set to OFF by mysqld if a session closed.
5) Y, but the data file will be truncated when recovery done and do a checkpoint.
6) I can add checksum based on my patch

BTW, based this patch, we have backed up many TokuDB instances whoes datasets are about 1.5TB(raw size is 6TB).
After all, this is a NOT BAD one.