Example mmpmon scenarios and how to analyze and interpret their results

This topic is an illustration of how mmpmon is used to analyze I/O data and draw conclusions based on it.

The fs_io_s and io_s requests are used to determine a number of GPFS™ I/O parameters and their implication for overall performance. The rhist requests are used to produce histogram data about I/O sizes and latency times for I/O requests. The request source and prefix directive once allow the user of mmpmon to more finely tune its operation.

Parent topic: Monitoring GPFS I/O performance with the mmpmon command
Related concepts:
Overview of mmpmon
Understanding the node list facility
Understanding the request histogram facility
Understanding the Remote Procedure Call (RPC) facility
Related tasks:
Specifying input to the mmpmon command
Display I/O statistics per mounted file system
Display I/O statistics for the entire node
Reset statistics to zero
Displaying mmpmon version
Related reference:
Other information about mmpmon output