单项选择题 A customer has an EMC Symmetrix DMX3000 that is at the end of lease. The environment consists of IBM System p， IBM System i， and IBM System z. The customer is evaluating EMC，   HDS， and IBM storage as possible replacements. They are interested in comparing the performance of all three disk subsystems.  Which tool compares performance（）

单项选择题 A customer wants to collect performance data from a newly installed IBM System Storage DS8700 to determine if the system meets expected benchmarks using their application test data.  Which tool best gathers the performance data（）

单项选择题 A company has acquired another company and is consolidating data centers. During the consolidation， half of the users of a business critical application lost access. The users who maintained access experienced slow performance.  What is the first action the SAN/storage administrator should take to determine the source of the problem（）