CA MICS Hardware and SCP Analyzer (RMF) Queries › Mainframe CPC Memory Use and Paging

Mainframe CPC Memory Use and Paging

This section contains the following topics:

RMFFRM - z/OS Central Storage Daily Frame Use by SYSID

RMFPAG - z/OS System Daily Paging Analysis

RMFFRM – z/OS Central Storage Daily Frame Use by SYSID

Overview

The RMFFRM query shows how central storage 4k page frames are used for each z/OS LPAR in each Central Processing Complex (CPC). The query produces five data extracts. The primary data extract provides a view of overall average central storage page frame usage at the RMF interval level (DETAIL timespan) or hourly level (DAYS timespan). The view uses vertical bars, stacked by central storage frame type. A horizontal reference line shows the total central storage page frames available to the LPAR. The white space between the top of the bars and the horizontal reference line represents available central storage page frames. The four additional data extracts show the minimum, average, and maximum page frame usage for four categories of storage types: CSA, LPA, Private, and SQA.

The first chart above shows interval level (15 minute) page frame use for a z/OS LPAR running on an IBM z/10 2097-712 CPC.

The second chart shows the minimum, average, and maximum fixed and pageable frame usage for private central storage frames on the same LPAR and CPC.

Uses

These charts show how z/OS LPARs use the real memory in central storage. Lack of sufficient real memory to handle workload requirements can result in excessive paging between central storage and auxiliary storage—which results in less than optimal performance. These charts help to understand how real memory is used, and can assist in identifying systems that are experiencing performance degradation due to insufficient central storage to satisfy workload requirements.

Data Extracts

z/OS Central Storage Daily All Frame Use

Left Y-axis

PAGAVP – Avg CSA Frames

PAGAVC – Avg CSA Fixed Frames

PAGAVLP– Avg LPA Frames

PAGAVLF – Avg LPA Fixed Frames

PAGAVQ – Avg SQA Fixed Frames

PAGAVLS – Avg LSQA Fixed Frames

PAGFIN – Frames in Nucleus

PAGAVR – Average Private Fixed Frames

PAGAVS – Avg Private Space Pageable Frames

Right Y-axis

PAGAVT – Avg Total Frames

X-axis

HHMM – Hour : Minute

Data element HHMM is derived by concatenating the HOUR and MINUTE of each RMF interval together, separated by a colon, HH:MM (for example, 14:59 meaning hour 14, 59th minute).

z/OS Central Storage Daily CSA Frame Use

Left Y-axis

PAGMNC – Min CSA Fixed Frames

PAGAVC – Avg CSA Fixed Frames

PAGMXC – Max CSA Fixed Frames

PAGMNP – Min CSA Frames

PAGAVP – Avg CSA Frames

PAGMXP – Max CSA Frames

X-axis

HHMM – Hour : Minute

Data element HHMM is derived by concatenating the HOUR and MINUTE of each RMF interval together, separated by a colon, HH:MM (for example, 14:59 meaning hour 14, 59th minute).

z/OS Central Storage Daily LPA Frame Use

Left Y-axis

PAGMNLF – Min LPA Fixed Frames

PAGAVLF – Avg LPA Fixed Frames

PAGMXLF – Max LPA Fixed Frames

PAGMNLP – Min LPA Frames

PAGAVLP – Avg LPA Frames

PAGMXLP – Max LPA Frames

X-axis

HHMM – Hour : Minute

Data element HHMM is derived by concatenating the HOUR and MINUTE of each RMF interval together, separated by a colon, HH:MM (for example, 14:59 meaning hour 14, 59th minute).

z/OS Central Storage Daily Private Frame Use

Left Y-axis

PAGMNS – Min Private Space Pageable Frames

PAGAVS – Avg Private Space Pageable Frames

PAGMXS - Max Private Space Pageable Frames

PAGMNR – Min Private Fixed Frames

PAGAVR – Average Private Fixed Frames

PAGMXR – Max Private Fixed Frames

X-axis

HHMM - Hour : Minute

Data element HHMM is derived by concatenating the HOUR and MINUTE of each RMF interval together, separated by a colon, HH:MM (for example, 14:59 meaning hour 14, 59th minute).

z/OS Central Storage Daily SQA Frame Use

Left Y-axis

PAGMNQ – Min SQA Fixed Frames

PAGAVQ – Avg SQA Fixed Frames

PAGMXQ – Max SQA Fixed Frames

PAGMNLS - Min LSQA Frames

PAGAVLS – Avg LSQA Frames

PAGMXLS – Max LSQA Frames

X-axis

HHMM – Hour : Minute

Data element HHMM is derived by concatenating the HOUR and MINUTE of each RMF interval together, separated by a colon, HH:MM (for example, 14:59 meaning hour 14, 59th minute).

Query Defaults

• HARCPU DETAIL timespan file: Cycles 01 - 02
• SCPPAG DETAIL timespan file: Cycles 01 - 02
• Filters: None
• User code excludes today’s data (IF DATEPART(ENDTS) EQ TODAY()-1 ;
• Derivations:

  CPCID

  TRIM(LPCMOD)||'-'||TRIM(CPCMODID)||'-Serial: '||SUBSTR(CPCSEQNB,12,5);
  

  DATE

  DATEPART(ENDTS);
  

  HHMM

  PUT(HOUR(ENDTS),Z2.) || ':' || PUT(MINUTE(ENDTS),Z2.);
  

Modifications

The following modifications can be made to the RMFFRM query:

• If you want to see hourly, rather than interval level page frame use, you can use the HARCPU and SCPPAG DAYS timespan.
• You can increase the number of cycles to create charts for multiple days, but comment out the user code in the initial file selection steps that select only yesterday’s data.
• You can use a filter statement to restrict data to focus on a particular time range (for example, HOUR GE 8 AND HOUR LE 17) or particular time zone (for example, ZONE EQ 1)
• You can add filter statements to select only a single CPC, or set of CPCs using the identifying data elements shown in the CPCID derivation.
• An additional temporal data element, DATEHHMM – Date Hour Minute, is provided and can be used to create single charts spanning multiple days. The key selection task for the data extract steps must be modified to substitute DATEHHMM for DATE and HHMM. Next, the user code in the initial file selection for the SCPPAG file must be commented out—it restricts processing to use yesterday’s data only. Finally, the cycles selected for the SCPPAG file must be increased to read in the number of days to chart. This is useful to see changes in frame usage before and after changes to the amount of central storage assigned to z/OS LPARs.