The CPU Service Unit (SU) is a conversion of the CMF CPU
time using a conversion factor that is specific to the processor where
the transaction is executed.
CPU service unit factors provide a standardized unit for measuring
CPU consumption that allows for the inherent differences in processors.
By specifying the CPU SU conversion factor in CICS PA, CMF CPU times
can be converted to a common unit of measurement: service units. This
allows you to more accurately compare workload performance when it
is being performed on different processors, and to provide consistent
measurement for SLA and chargeback.
Reporting with the CPUSU derived field
The
derived field CPUSU is available in List, ListX, and Summary Forms
and List and Summary Templates.
You can report and extract converted
values from HDBs either by specifying CPUSU in the Template and thereby
loading it in the HDB or by specifying it in the Form. If the HDB
is loaded with the CPUSU value, it will be reported and extracted
as for any other field. In this case, the specification of the conversion
factor in either the definition or file will be ignored. If on the
other hand derived field CPUSU was not loaded into the HDB but is
specified in the Form and the CPU field is in the HDB, the conversion
factor will be used to calculate CPUSU value.
Attention: - Reporting CPUSU for a Summary HDB that was not loaded with the
CPUSU value has a potential risk which might render the CPUSU value
incorrect. This will occur when the summarized data in the HDB comes
from Images with different CPU SU conversion factors. This means that
a single CPU SU conversion factor does not apply to all transactions
in the summarized data. To avoid this problem, ensure that all summarized
transactions are eligible to use the same CPU SU conversion factor.
- The specification of the CPUSU value in functions such as Selection
Criteria and Form Range must include a decimal point. Not specifying
a decimal value will result in the value being interpreted as a decimal
fraction.
Rules for applying conversion factors
CPU SU conversion factors can be specified in
two places:
- As an image-specific value defined in the repository (Definition)
- As a file-specific value specified in the CICSPA command suboperand
SUFACTOR (File).
The following rules govern their application.
- File and Definition conversion factors cannot be combined in the
execution of a single CICSPA command. If File conversion factors are
specified, any Definition conversion factors are all ignored.
- File conversion factors are specific to each file and can be specified
for individual IN ddnames or log stream names.
- If an IN ddname is a concatenation of multiple SMF files, the
specified conversion factor will apply to all files in the concatenation.
- If multiple SUFACTOR operands refer to the same ddname or HDB
name, only the first SUFACTOR conversion factor will be used for the
input.
- If one or more file SUFACTOR values are specified then any ddname
or input without an SUFACTOR takes the current processor default.
- In case of HDB reporting, the SUFACTOR will be available as an
operand and will apply to all containers included in the report. In
other words, there will not be a container-specific conversion factor
specified or applied.