Mainframe prerequisites

The mainframe system on which the Db2 Query Monitor monitoring agent, Query Monitor Subsystem, ISPF client, and CAE Agent run must meet these requirements.

  • IBM® z/OS® Version 2.4
  • IBM Tools Customizer for z/OS 01.01.00 (PTF UI80211)
  • Db2 Version 12.1 and later, until end of support for the given Db2® version
  • IBM SMP/E for z/OS V3.6 (5655-G44) or later
  • IBM Db2 Data Access Common Collector for z/OS V1.1 (5639-OLC) or later
  • ISPF Version 4 and later
  • z/OS support for Unicode. The installation of z/OS support for Unicode with SMP/E is described in z/OS Planning for Installation (GA22-7504).
  • There is no restriction running Db2 Query Monitor with Extended Address Volumes (EAV) 223GB volumes.
  • Hardware support of zSeries-6 to support the zEC12 instructions is needed for Db2 AI feature

Calculating Db2 Query Monitor CPU usage

Db2 Query Monitor CPU overhead is not reflected in the Db2 Query Monitor started tasks. Overhead for Db2 Query Monitor started tasks is normally insignificant and consistent. Db2 Query Monitor use intercepts into the Db2 address space to monitor and collect the SQL performance metrics. This method is efficient but because it takes place in the Db2 Address Space you must look in the Db2 Application CPU to visualize any CPU overhead caused by Db2 Query Monitor's collection of SQL performance metrics. This can be done by collecting Db2 accounting and statistics traces and report the Db2 class 2 CPU time. Collect the tracing when Db2 Query Monitor is active and when it is inactive. Compare the results to calculate the cost of running Db2 Query Monitor.

Starting Db2 Query Monitor collector address space

Query Monitor is designed to utilize 64-bit storage, so the 24-bit storage is minimal outside the z/OS required control blocks (the majority of which are system-controlled). The 31-bit storage that is used more than 24-bit is still limited to programs and transitory buffers.

When REGION= specifies a value less than 16M, the specified value will represent the amount of memory below the 16 Megabyte "Line" with 32 Megabytes of storage available between the 16 Megabyte "Line" and 2 Gigabyte "Bar".

Since Query Monitor primarily uses 64-bit storage, the amount of 24-bit storage is minimal, and 32M is enough for 31-bit storage. Hence, 6M or less is sufficient for running the CQM collector.