Redis BGSAVE command saves the DB in the background. The OK code is immediately returned. Redis forks, the parent continues to serve the clients, the child saves the DB on the disk, then exits. A client may be able to check if the operation succeeded using the LASTSAVE command.
Simple string reply.
Following is the basic syntax of Redis BGSAVE command.
redis 127.0.0.1:6379> BGSAVE