Identify and resolve common performance problems

Many different performance problems often affect common areas of the iSeries™ server. Learn how to research and resolve problems in common areas, for example, backup and recovery.

When performance problems occur on the iSeries server, they often affect certain areas of the system first. Refer to the following table for some methods available for researching performance on these system areas. Many of these areas are available as system monitor metrics. However, there are several other ways to access information about them.

Area Description Available tools
Processor load Determine if there are too many jobs on the system or if some jobs are using a large percentage of processor time.
  • Work with Active Jobs (WRKACTJOB) command.
  • Work with System Activity (WRKSYSACT) command, which is part of Performance Tools licensed program.
  • The work management function in iSeries Navigator.
  • CPU utilization metrics within the iSeries Navigator system monitor.
  • Work with Disk Status (WRKDSKSTS) command.
Main storage Investigate faulting and the wait-to-ineligible transitions.
  • Disk storage metrics within the iSeries Navigator system monitor.
  • Work with System Status (WRKSYSSTS) command.
  • The Memory Pools function under Work Management in iSeries Navigator.
Disk Determine if there are too few arms or if the arms are too slow.
  • Work with Disk Status (WRKDSKSTS) command.
  • Disk arm utilization metrics within the iSeries Navigator system monitor.
  • Performance Tools System and Component report.
Communications Find slow lines, errors on the line, or too many users for the line.
  • Performance Tools Component Report.
  • LAN utilization metrics within the iSeries Navigator system monitor.
IOPs Determine if any IOPs are not balanced or if there are not enough IOPs.
  • Performance Tools Component Report.
  • IOP utilization metrics within the iSeries Navigator system monitor.
Software Investigate locks and mutual exclusions (mutexes).
  • Performance Tools Locks report.
  • Performance Tools Trace report.
  • Work with Object Locks (WRKOBJLCK) command.
  • In iSeries Navigator, right-click on the suspect job under Work Management, and select Details > Locked Objects.
  • Start of changeWRKSYSACT Option 6.End of change
  • Start of changeDSPPFRDTA. F6, Option 6.End of change
Backup and recovery Investigate areas that affect backup and recovery and save and restore operations.
  • iSeries Performance Capabilities Reference (Save/Restore Performance chapter).
  • Why does my backup take so long after I restart my server?
  • Why do my backups take longer after I upgrade to a new release?
  • Why do my backups take longer after I change hardware on my server?
Related concepts
Work management function in iSeries Navigator
Related reference
Monitor metrics
Frequently asked questions
Related information
iSeries Performance Capabilities Reference (Save/Restore Performance chapter)