Finding wait statistics for a job, task, or thread

During the running of a job, task, or thread, conditions arise that cause that process to wait (for example, while the system resolves a lock or hold on a required object).

Collection Services can collect data on the cause and duration of the time a process spends waiting. This data is reported in the Collection Services database files QAPMJOBWT and QAPMJOBWTD.

Note: To query the QAPMJOBWTD file, the CCSID of your job must be set to the CCSID of the primary language installed on the system (not to 65535 binary data).

Another tool that shows job wait statistics is IBM® i5/OS Job Watcher. IBM i5/OS Job Watcher returns real-time information about a selected set of jobs, threads, and Licensed Internal Code (LIC) program tasks. At specified time intervals, IBM i5/OS Job Watcher samples anywhere from one thread per job to all threads per job. IBM i5/OS Job Watcher gathers a variety of performance data, including detailed wait statistics for jobs, tasks, and threads.

There are 32 wait buckets which accumulate wait state data. These static wait buckets, used by both Collection Services and IBM i5/OS Job Watcher, provide a stable view of the wait state data. In Collection Services, data from these buckets is reported in files QAPMJOBWT and QAPMJOBWTG. In Job Watcher, data from these buckets is reported in QAPYJWTDE and QAPYJWSTS.