Interpreting the RMF workload activity data

An RMF™ workload activity report contains "snapshot data" which is data collected over a relatively short interval. The data for a given work request (CICS® transaction) in an MRO environment is generally collected for more than one CICS region, which means there can be some apparent inconsistencies between the execution (EXE) phase and the begin to end (BTE) data in the RMF reports. This is caused by the end of a reporting interval occurring at a point when work has completed in one region but not yet completed in an associated region.

Figure 45 illustrates this.

Figure 45. Illustration of snapshot principle for RMF reporting intervals
 During a particular RMF reporting interval, a transaction TxnA is started in the TOR, and routed to the AOR. Still in that reporting interval, the AOR runs and completes TxnA. TxnA is therefore included in the EXE (execution) total for that reporting interval. Now the RMF reporting interval ends, and a new interval begins. During the new interval, TxnA returns to the TOR, where it is completed. TxnA is therefore included in the BTE (beginning-to-end) total for the new reporting interval.

For example, an AOR can finish processing transactions, the completion of which are included in the current reporting interval, whilst the TOR may not complete its processing of the same transactions during the same interval.

Figure 46 shows an example of the CICS state section of an RMF Monitor I workload activity report. It is based on an example hotel reservations service class.

The text following the figure explains how to interpret the fields.

RMF reporting intervals

Figure 46. Hotel Reservations service class
REPORT BY: POLICY=HPTSPOL1  WORKLOAD=PRODWKLD SERVICE CLASS=CICSHR RESOURCE GROUP=*NONE PERIOD=1 IMPORTANCE=HIGH
 
-TRANSACTIONS--  TRANSACTION TIME   HHH.MM.SS.TTT
AVG        0.00  ACTUAL             000.00.00.114
MPL        0.00  QUEUED             000.00.00.036
ENDED       216  EXECUTION          000.00.00.078
END/SEC    0.24  STANDARD DEVIATION 000.00.00.270
#SWAPS        0
EXECUTD     216
 
           --------------------------RESPONSE TIME BREAKDOWN IN PERCENTAGE-------------------  ----STATE------
SUB   P  TOTAL  ACTIVE  READY IDLE  -------------------------WAITING FOR---------------------  SWITCHED TIME (%)
TYPE                                LOCK I/O  CONV  DIST LOCAL SYSPL  REMOT TIMER  PROD  MISC  LOCAL SYSPL REMOT
CICS BTE  93.4   10.2   0.0   0.0   0.0  0.0  83.3   0.0  0.0   0.0    0.0   0.0    0.0   0.0   83.3  0.0   0.0

CICS EXE  67.0   13.2   7.1   0.0   0.0  0.0   0.0   0.0  0.0   0.0    0.0   0.0   46.7   0.0    0.0  0.0   0.0
 

The fields in this RMF report describe an example CICS hotel reservations service class (CICSHR), explained as follows:

SUBTYPE: CICS
This field indicates that the subsystem work manager is CICS.
P: BTE
This field indicates that the data in the row relates to the begin-to-end work phase.

CICS transactions are analyzed over two phases: a begin-to-end (BTE) phase, and an execution (EXE) phase.

The begin-to-end phase usually takes place in the terminal owning region (TOR), which is responsible for starting and ending the transaction.

P: EXE
This field indicates that the data in the row relates to the execution work phase. The execution phase can take place in an application owning region (AOR) and a resource-owning region such as an FOR. In our example, the 216 transactions were routed by a TOR to another region for execution, such as an AOR (and possibly an FOR).
ENDED
This field shows that 216 hotel reservation transactions completed.
EXECUTD
This field shows that the AORs completed 216 transactions in the reporting interval.
Note:
In our example the two phases show the same number of transactions completed, indicating that during the reporting interval all the transactions routed by the TORs (ENDED) were completed by the AORs (EXECUTD) and also completed by the TORs. This will not normally be the case because of the way data is captured in RMF reporting intervals. See RMF reporting intervals.
ACTUAL
Shown under TRANSACTION TIME, this field shows the average response time as 0.114 seconds, for the 216 transactions completed in the BTE phase.
EXECUTION
Shown under TRANSACTION TIME, this field shows that on average it took 0.078 seconds for the AORs to execute the transactions.

While executing these transactions, CICS records the states the transactions are experiencing. RMF reports the states in the RESPONSE TIME BREAKDOWN IN PERCENTAGE section of the report, with one line for the begin-to-end phase, and another for the execution phase.

The response time analysis for the BTE phase is described as follows:

For BTE
Explanation
TOTAL
The CICS BTE total field shows that the TORs have information covering 93.4% of the ACTUAL response time, the analysis of which is shown in the remainder of the row.
ACTIVE
On average, the work (transactions) was active in the TORs for only about 10.2% of the ACTUAL response time
READY
In this phase, the TORs did not detect that any part of the average response time was accounted for by work that was dispatchable but waiting behind other transactions.
IDLE
In this phase, the TORs did not detect that any part of the average response time was accounted for by transactions that were waiting for work.
WAITING FOR
The WAITING FOR section includes values for LOCK, I/O, CONV, DIST, LOCAL, SYSPL, REMOT, TIMER, PROD and MISC. In this report, only one field shows a value in the WAITING FOR section--the CONV value (this is typical for a TOR). It indicates that for about 83.3% of the time, the transactions were waiting on a conversation. This is further explained by the SWITCHED TIME data.
SWITCHED TIME
From the SWITCHED TIME % data, which has values for LOCAL, SYSPL and REMOT, you can see the reason for the ‘waiting-on-a-conversation’. This is 83.3 % LOCAL, which indicates that the transactions were routed locally to an AOR on the same MVS™ image.
Note:
In the analysis of the BTE phase, the values do not exactly add up to the TOTAL value because of rounding--in our example, 10.2 + 83.3 = 93.5, against a total shown as 93.4.

The response time analysis for the EXE phase is described as follows:

For EXE
Explanation
TOTAL
The CICS EXE total field shows that the AORs have information covering 67% of the ACTUAL response time.
ACTIVE
On average, the work is active in the AOR for only about 13.2% of the average response time.
READY
On average the work is ready, but waiting behind other tasks in the region, for about 7.1% of the average response time.
PROD
On average, 46.7% of the average response time is spent outside the CICS subsystem, waiting for another product to provide some service to these transactions.

You can't tell from this RMF report what the other product is, but the probability is that the transactions are accessing data through a database manager such as Database Control (DBCTL) or DB2®.

The following sections give some examples of possible data that may be reported for CICS and IMS™ in an RMF workload activity report, and some possible explanations for the data.

Related concepts
Using CICS monitoring information with RMF
Terms used in RMF reports
An explanation of the difference between a DFHSTUP transaction report and an RMF workload report
RMF report examples:
RMF report example: very large percentages in the response time breakdown
RMF report example: response time breakdown data is all zero
RMF report example: execution time greater than response time
RMF report example: large SWITCH LOCAL Time in CICS execution phase
RMF report example: fewer ended transactions with increased response times
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