BGSAVE
Syntax
BGSAVE [SCHEDULE] [RDB|DF] [cloud_uri] [filename]
Time complexity: O(1)
ACL categories: @admin, @slow, @dangerous
Equivalent to SAVE and kept for compatibility reasons.
The optional SCHEDULE subcommand is accepted for client compatibility but is a no-op: concurrent saves are still rejected and saves are not queued.
Return
Simple string reply: OK. Dragonfly replies with a plain OK for BGSAVE (including when invoked with the SCHEDULE subcommand), not the Redis-style Background saving started / Background saving scheduled strings.