Pipelines
In Redis, a pipeline is a way to send multiple commands together to the Redis server without waiting for individual replies. The replies are read all at once by the client. The time taken for a Redis client to send a command and obtain a reply from the Redis server is called Round Trip Time (RTT). When multiple commands are sent, there are multiple RTTs.
Pipelines can decrease the number of RTTs because commands are grouped, so a pipeline with 10 commands will have only one RTT. This can improve the network's performance significantly.
For instance, if the network link between a client and server has an RTT of 100 ms, the maximum number of commands that can be sent per second is 10, no matter how many commands can be handled by the Redis server. Usually, a Redis server can handle hundreds of thousands of commands per second, and not using pipelines may be a waste of resources.
When Redis is used without pipelines, each command needs to wait for a reply. Assume the following...