IBM i Disk Watcher

IBM® i Disk Watcher provides for the collection of disk performance data to diagnose disk related performance problems.

IBM i Disk Watcher allows you to obtain data concerning I/O operations to disk units, along with frequently needed run-time data to determine which objects, files, processes, threads, and tasks are being accessed. This tool surfaces data beyond what is provided by such tools as WRKDSKSTS, WRKSYSSTS, and WRKSYSACT. Disk Watcher provides a mechanism to use short and longer duration traces to collect disk I/O data along with the associated task and object name.

Some potential uses of this tool are:

  • Evaluating the performance of I/O operations on multi-path disk units
  • Evaluating the performance of I/O queuing
  • Determining how performance may be improved by re-spreading data across units
  • Determining the optimal placement of devices, IOAs, or buses

IBM i Disk Watcher can be configured and managed through the IBM Navigator for i Performance interface or CL commands.