Sampling data and producing records
The Extractor executes samplers to monitor hardware usage (CPU, channel paths, I/O queuing, and I/O devices) and software activity (the SRM, paging, enqueue contention, TSO usage, and common storage allocations), as well as other system resource information.
A sampler is a program module that creates data by using one of the following methods of measuring the performance of a specific area of your system:
- DIE (disabled interrupt exit)
- SRB (service request block)
- SRM (System Resources Manager)
- TCB (task control block)
Each sampler uses one or more of the four sampling methods to collect this data.
A sampler executes only when a corresponding Extractor control statement is defined in the Extractor JCL. (For more information, see Defining-Extractor-control-statements.) The manner in which each sampler executes is controlled by parameters associated with each Extractor control statement. (For more information, see How Extractor statements control sampler operations.)
As a sampler gathers information, the data gets accumulated in CSA. At the end of the interval time for the CPM or IPM monitoring mode, another function of the Extractor writes the data collected in CSA as records to SMF or CMF data sets. (For more information about monitoring modes, see When to use CMF MONITOR Extractor CPM and IPM modes. For more information about writing records, see Writing-records.)
Methods of sampling data
The Extractor uses four sampling methods to collect data.
DIE | Disabled Interrupt Exit—CMF keeps the time spent in the DIE samplers to a minimum to avoid degrading system performance |
|---|---|
SRB | System Request Block—several samplers use the SRB sampling method |
Under SRB, higher resolution sampling is provided and system interrupts can still be honored. | |
SRM | System Resources Manager—the SRM event-counting method is used for sampling functions that are driven directly by SYSEVENTs (such as TSO or ENQUEUE) |
SRM sampling is driven by an event, not a time value. | |
TCB | Task Control Block—a separate subtask that can be dispatched on any processor, when required, by internal data-gathering mechanisms in the operating system |
How Extractor statements control sampler operations
Most of the Extractor statements provide you with parameters that allow you to control the manner in which a particular sampler functions.
Extractor statements that do not provide you with parameters are typically for samplers that are event-driven and, therefore, function only when the particular circumstance occurs in your system.
Parameters affect sampler operations such as the rate frequency at which a sampler gathers measured data and places it in CSA. System components can be measured at different user-selected sampling rates; for example, device activity can be sampled once a second, while CPU activity can be sampled 10 times a second.
Other parameters in Extractor control statements allow you to control the scope of resources being monitored, the type of information being collected, and many other data-gathering options.
All of this control through statement parameters is provided so that you can tune the Extractor samplers to collect only the data your site requires, which allows the Extractor to perform its monitoring functions on your system in the most efficient manner possible.
The sampling functions occur continuously. All samplers write out records based on the recording interval, with the exception of the sampler for the REPORT (GBLS sampler) Extractor control statement:
The GBLS sampler writes records more frequently due to the volume of data that it is recording.
Record types
The Extractor samplers produce records that can be processed later by the CMF Analyzer or by the RMF postprocessor, or used by other BMC Software products.
The SMF and CMF user record types produced by CMFMON and by the Extractor for the CMF MONITOR Analyzer are shown in the table in Numeric list of SMF record types. User programs that are written to process SMF record types, such as MICS, MXG, or SLR, can process CMF MONITOR records.
Changing the default CMF record type ID
A default CMF user record SMF ID of 240 is used. This default value can be changed, however, by defining a different ID value at the SMFRECID parameter of the REPORT control statement.
Numeric list of SMF record types
The table below shows the SMF record types used by CMF MONITOR in ascending numeric order.
SMF record types with corresponding Extractor statements and samplers
Record type | Description | Sampler | Control statement |
|---|---|---|---|
SMF 42-6 | Dataset Activity (SMF 42-6 records are created by SMS, and not CMF.) | not applicable | not applicable |
SMF 70-1 | CPU activity | CPUS | CPU |
SMF 70-2 | Cryptographic activity | CRYS | CRYPTO |
SMF 71 | paging activity | PAGS | PAGING |
SMF 72-3 | workload activity by service class | WLMS | WORKLOAD |
SMF 72-4 | resource usage and delay data by service class/period1 | PGDS | PGDDLAY |
SMF 72-5 | serialization delay data | LOCK | LOCKDATA |
SMF 73 | channel activity | CHNS | CHANNEL |
SMF 74-1 | device activity | DEVS | DEVICE |
SMF 74-2 | Cross-System Coupling Facility (XCF) data | XCFS | XCFDATA |
SMF 74-3 | Open Edition MVS data | OMVS | OMVS |
SMF 74-4 | coupling facility data1 | CFTS | CFDATA |
SMF 74-5 | cache data records | CA3H CA5H CA6H | CACHE |
SMF 74-6 | HFS statistics | HFSS | HFS |
SMF 74-7 | FICON Director statistics | FCSW | FICONSW |
SMF 74-8 | Enterprise Storage Server (ESS) statistics | CA3H CA5H CA6H | CACHE |
SMF 74-9 | PCI Express (PCIe) data | PCIE | PCIEDATA |
SMF 75 | page data set activity | ASMS | ASMDATA |
SMF 76 | system control block trace data | TRAS | TRACE76 |
SMF 77 | enqueue activity This sampler does not run in IPM mode. | EQES | ENQUEUE |
SMF 78-2 | virtual storage data | VSMS | VSMDATA |
SMF 78-3 | I/O queuing data for 3090, ES/9000 series, or later processors | IOQS | IOQ |
SMF 79-1 | address space state data | not applicable | ASD |
SMF 79-2 | address space resource data | not applicable | ARD |
SMF 79-3 | central storage/processor/SRM activity | not applicable | SRCS |
SMF 79-4 | system paging activity data | not applicable | SPAG |
SMF 79-5 | address space SRM data | not applicable | ASRM |
SMF 79-6 | enqueue reserve data | not applicable | SENQR |
SMF 79-7 | enqueue contention data | not applicable | SENQ |
SMF 79-9 | device activity data | not applicable | DEVICE |
SMF 79-11 | page data set activity | not applicable | PGSPP |
SMF 79-12 | channel path activity | not applicable | CHANNEL |
SMF 79-14 | I/O queuing activity by logical control unit for the 3090, ES/9000 series processors CMFMON | not applicable | IOQ |
SMF103-1 SMF103-2 | HTTP Server Report | not applicable | not applicable |
SMF108-1 SMF108-3 | LOTUS DOMINO Server Report | not applicable | not applicable |
CMF 240-00 | SRM constants, installation performance specifications, and Extractor control cards data | RECD | REPORT |
CMF 240-01 | CPU data | CPUS | CPU |
CMF 240-02 | ASM data | ASMS | ASMDATA |
CMF 240-03 | paging data | PAGS | PAGING |
CMF 240-05 | device data | DEVS | DEVICE |
CMF 240-06 | Extractor summary data2 | EXTS | EXTSUM |
CMF 240-09 | ASM data | ASMS | ASMDATA |
CMF 240-11 | global bit map | GBLS | REPORT |
CMF 240-16 | LPA mapping data | LPAM | LINKMAP |
CMF 240-18 | CMF trace record data | TRCE | TRACE |
CMF 240-20 | TSO command summary record data | TSOS | TSODATA |
CMF 240-21 | TSO user summary record data | TSOS | TSODATA |
CMF 240-24 | disabled time sampling record data | DITS | DISTIM |
CMF 240-29 | common storage usage by jobs2 | CSMS | CSMON |
CMF 240-50 | output writer statistics data | not applicable | not applicable |
CMF 240-98 | used to identify invalid records | not applicable | not applicable |
CMF 240-99 | used to identify invalid records | not applicable | not applicable |
1 This sampler does not function unless the MVS PAS data collectors are active.
2 This sampler does not run in IPM mode.
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