A customer using an IBM System Storage DS8300 is facing performance problems. After the analysis by the technical specialist， the diagnosis indicates that the cache hits may be improved by a cache upgrade. How can the system be monitored in order to check the benefits of the cache upgrade（）
- Ausing the "vmstat" command on the AIX servers connected via SAN to the DS8300 system
- Blooking at the number of I/O managed by the DS8300 system
- Creading the performance reports via TotalStorage Productivity Center for Disk
- Dgenerating reports using the TotalStorage Expert