当应用系统性能变慢的时候，系统管理员可能认为是FC SAN的问题导致。存储管理员可以直接登录SanScout平台，实时监控影响应用系统的Initiator - Target - LUN的性能参数。

SanScout目前对于I/O支持如下的性能相关参数：

读命令 （READ CMD）

• Read commands issued
• Read commands completed
• min read size
• max read size
• Read data MB / sec
• Read data frames / sec
• Min cmd to First Data time (ms)
• Max cmd to First Data time (ms)
• Avg cmd to first data time (ms)
• Min last data to response  time (ms)
• Max last data to response  time (ms)
• Avg  last data to response time (ms)
• min read exchange completion time (ms)
• Max read exchange completion time (ms)
• Avg Read exchange completion time (ms)

写命令 （WRITE CMD）

• Write commands issued
• Write commands completed
• Min Write size
• Max Write size
• Write MB /s
• Write data frames /sec
• Min cmd to transfer_ready time (ms)
• Max cmd to transfer_ready time (ms)
• Avg cmd to transfer_ready a time (ms)
• Min  transfer_ready to first data time (ms)
• Max  transfer_ready to first data time (ms)
• Avg transfer_ready to first data time (ms)
• Min last data to response  time (ms)
• Max last data to response  time (ms)
• Avg last data to response time (ms)
• min write exchange completion time (ms)
• Max write exchange completion time (ms)
• Avg Write exchange completion time (ms)