Measure Reference Manual

These DEFINE statements do not impact the startup time for small measurements.
• The CID table is an internal structure that determines how many entities can be measured. The
table assigns one counter identifier (CID) to each measured entity. For example, if you request
measurement of five different files, the CID table assigns one CID per file, no matter how many
counters the measurement includes for each file.
In Measure G05 and earlier PVUs, the CID table has an upper limit of 32,000 CIDs per
processor. In product versions D45, G05, and later, you can increase the CID table limit
according to the DEFINE statements, shown below. In H-series and J-series RVUs, the default
size of the CID table is 64,000 CIDs per processor.
To increase the CID table limit, issue one of these DEFINE statements before launching
MEASCOM and issuing the START MEASSUBSYS command. Note:
◦ Table limits of 192,000 and 256,000 CIDs are valid only in H-series and J-series RVUs.
◦ Table limits of 512,000 CIDs are valid only in Measure H04/J02 and later PVUs.
◦ Table limits of 1,024,000 CIDs are valid only in H06.25/J06.14 and later RVUs.
> ADD DEFINE =_SET_MAX_CIDS_TO_64000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_96000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_128000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_192000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_256000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_512000, file a
> ADD DEFINE =_SET_MAX_CIDS_TO_1024K, file a
The file a parameter is required for syntactical correctness but is not used by Measure.
MEASCOM calls MEASMONCONTROL to start the Measure subsystem with the DEFINE in
effect.
For each additional 32,000 CIDs below 512,000 CIDs, the Measure performance monitor
requires an additional 3.5 megabytes of memory for CIDs and 6.5 megabytes for counter
space (a total of 10 megabytes) for each CPU. For 512,000 CIDs, the counter space is about
105 megabytes. For 1,024,000 CIDs, the counter space is about 123 megabytes. Increasing
the CID table limit might have a noticeable impact on system performance.
Usage Notes for H-Series and J-Series PVUs and RVUs
• In H06.20/J06.09 and later RVUs, the error messages for the START MEASSUBSYS command
might appear as
Process_Create_ error MM (NN) from Measmoncontrol
where:
MM
is the error returned from Process_Create_.
NN
is the error-detail returned from Process_Create_ .
• In H06.14/J06.04 and later RVUs (with specific SPRs), you can configure the Measure
subsystem to emit the EMS warning event 4063 to indicate that the per-CPU CID usage exceeds
a configured threshold. This behavior helps you monitor the number of CIDs, which directly
control the number of entities being measured at a given time. You can also look at the
ENDING-FREE-CIDS counter in the CPU record for the exact number of available CIDs. Use
the =_MEAS_EMIT_CID_USAGE DEFINE to configure the warning threshold for CID table
usage. When this threshold is exceeded, a 4063 warning event is emitted.
To configure a threshold, using the last two characters of the file name, specify the percentage
of CID table size that can be consumed prior to issuing a warning. For example, to request
START MEASSUBSYS 121