WarmUp pre-fills the connection pool regardless of any transactions. It is done to prepare the client to take big number of requests without having to open connections first and timing out on the first few batch of requests that have to either wait for opening a connection, or idle until a connection is available in the queue.
It is a new API, and if it is successful, it will be implemented in other clients later.
No, there is not a similar method in C#.
The WarmUp feature is not available in any other client.
Currently the WarmUp feature is only available in the Go Client.
Is there some reason it is only in the go version? Does Go not do well on startup, or do you suspect this is something that will be considered for other versions too?