When pg_basebackup starts, it tries to finish its work as quickly as possible. If you have a good network connection, pg_basebackup is definitely able to fetch hundreds of megabytes a second from the remote server. If your server has a weak I/O system, it could mean that pg_basebackup could suck up all the resources easily and end users might experience bad performance because their I/O requests are simply too slow.
To control the maximum transfer rate, pg_basebackup offers the following:
-r, --max-rate=RATE maximum transfer rate to transfer data directory (in kB/s, or use suffix "k" or "M")
When you create a base backup, make sure that the disk system on the master can actually stand the load. Adjusting ...
