You can use ziomon for performance problem determination and capacity planning.
The ziomon monitor collects FCP performance relevant data over a specified period of time. The monitor uses a block I/O layer tracing tool, blktrace. Monitoring data is written to disk periodically. ziomon builds up a history of monitoring data, which can be consumed and analyzed by other tools.
The ziomon monitor determines the FCP device that is used to access a SCSI device. The monitor collects performance data for both SCSI devices and corresponding FCP devices.