why to use batch?
When we have to send a lot of command to redis
Redis server have to process commands and replies about them.
In request - response mechanism, there’s also ‘Round Trip Time’.
Round Trip Time (RTT)
Why RTT makes process slow?
internet hops
If client and server communication using internet protocol
There’s many hops between them.
According to region, routing, many differences exist.
context switching
Redis client - server has TCP connection.
When sending command (client) and receiving the command (server), there’s socket read() , write() blocking system call.
So, a lot of context switching between user and kernel area in the server.
How to use pipeline batch
Redis has ‘pipeline’ command for batch commands. You should consider request reasonable number commands on it.
While the client sends commands using pipelining,
the server will be forced to queue the replies, using memory. If massive command in a single pipeline, there’s possibility of peeking memory usage on redis server.