With bit count of small files it will take few minutes for preparation and replication speed should be about 10MB/s if all conditions are good (mem., nic, cpu...). Data Replication needs snapshot (is your snapshot approx 10% of the 2TB?) and lot of system memory. It is also operating on checksums so this need some time. In small count of big files it can
replicate with speeds of up to 40MB/s. I saw your email to support so this is what I found from other customers referencing to this subject.