Cache report

You may want to start with the Cache Summary report which provides a summary of all subsystems and a list of volumes that need special attention. Probably, you would select an interval with a very high I/O activity on your system. If this is during night shift between 8:00 PM and 10:00 PM on May 13, 2016, then you define

Example:

DATE(05132016,05132016)
RTOD(2000,2200)
REPORTS(CACHE(SUMMARY))

With this information, you can continue by either getting reports with some more details, or by creating an Overview report for the most interesting subsystems and devices.

You get a Subsystem Activity report for the SSIDs 0044 and 0058 with:

Example:

REPORTS(CACHE(SSID(0044,0058)))

If you see from the list of the top-20 devices that the volumes DATA01 with device number 06F3, DB2PRD with device number 0722, and CICS14 with device number 0734 have the highest cache miss rates in the reported interval, you can create an Overview report with several details for a longer period, for example, for two complete days:

Example:

DATE(05132016,05142016)
OVERVIEW(RECORD,REPORT)
OVW(DATA01A(CADRT(06F3)))
OVW(DATA01B(CADRHN(06F3)))
OVW(DATA01C(CADSTG(06F3)))
OVW(DB2PRDA(CADRT(0722)))
OVW(DB2PRDB(CADRHN(0722)))
OVW(DB2PRDC(CADSTG(0722)))
OVW(CICS14A(CADRT(0734)))
OVW(CICS14B(CADRHN(0734)))
OVW(CICS14C(CADSTG(0734)))

In this example, the Overview report will provide values about the total I/O rate, the read cache hit rate, and the DASD staging I/O rate. Refer to OVW for more information about the syntax of the OVW statement.