IBM Exam Questions

why does it show that a T67720 has only a sustained I/O performance and a TS7740 has a sustained AND

According to the IBM TS7700 Performance white paper, why does it show that a T67720 has only a sustained
I/O performance and a TS7740 has a sustained AND peak I/O performance?

A.
Disk is faster than tape

B.
A disk-based repository delivers more constant throughput rates

C.
The TS7740 has to do pre-migration tasks at a certain point of operation

D.
The TS7740 Fibre Channel disk cache does filesystem rebuilds from time to time