I have client that houses about 1.2TB of data backing up to disk, but it is backing up at extreamly slow rate. Some of my other clients backup at a rate of 29 t- 40 KBPS and my problem client only does about 5 KBPS. All of my clients are within my Data center(local LAN).
It feels like I should be pushing about the same data rate as the rest of my clinets.
Windows 2008 r2
Client NBU 7.1
When opening each files/folders, system call(or API) has some turn around time. It brings performance degration.
Check this thread, and try multistreaming, raw partition backup, or FlashBackup.