In this session, the speaker will talk about how MyRocks's online backups work. Both physical (myrockshotbackup) and logical (mysqldump) backups will be covered, and physical backups will be more focused. MyRocks (and RocksDB)'s physical backups basically work by 1. invoking RocksDB checkpoint that creates hard links then 2. copying data files (SST), redo logs (WAL) and others. myrockshotbackup has additional features like "renewing checkpoint" that makes replication catchup shorter, streaming backups, and auto-detecting O_DIRECT. Logical backups in MyRocks/RocksDB is more efficient than InnoDB because RocksDB more efficiently keeps track of transaction histories. How physical/logical MyRocks/RocksDB backups work are not widely discussed in public, and the speaker will demystify in this session.