Xtrabackup failed when doing incremental backup


I met an ERROR when doing incremental backup:

Error: failed to execute query FLUSH NO_WRITE_TO_BINLOG CHANGED_PAGE_BITMAPS: Access denied; you need (at least one of) the SUPER privilege(s) for this operation

I did the incremental backup with a user only have RELOAD and REPLICATION CLIENT privileges. I don’t want to give the backup user the SUPER privilege.

I did the full backup with the same user and it finished successfully. I didn’t know why I need SUPER privilege to do the incremental backup.

I appreciate if anyone can help me this out.