Duong,
If you can connect to the SVP Storage Navigator or locally log on to the SVP, you can start performance monitor (Report -> Performance Monitor).
Maybe you need first to enable monitoring on your CU's if you want to check per LDEV.
There you can check you for example your replication ports to see how much data is sent.
Other option is to check your replication switches.
Maybe this will help you,
Regards,
Marco