Overview of mmpmon

The mmpmon command allows the system administrator to collect I/O statistics from the point of view of GPFS servicing application I/O requests.

The collected data can be used for the following purposes:
  • Track I/O demand over longer periods of time - weeks or months.
  • Record I/O patterns over time (when peak usage occurs, and so forth).
  • Determine whether some nodes service more application demand than others.
  • Monitor the I/O patterns of a single application, which is spread across multiple nodes.
  • Record application I/O request service times.
Figure 1 shows the software layers in a typical system with GPFS. The mmpmon command is built into GPFS.
Figure 1. Node running the mmpmon command
This is a node with GPFS running the mmpmon command. It consists of four layers. The top layer is the application. The second layer is the operating system, either AIX or Linux. The third layer is GPFS with the mmpmon command as a subset of GPFS. The fourth layer is the NSD layer.