Collection
In principle, only the MTE classes of the systems to which a valid Collection and Reorganization Schema is assigned (see Assigning Collection and Reorganization Schemata to Performance Values) are collected in the Central Performance History (CPH). There are three methods of data transfer:
The performance values are read by the central system using RFC from the monitoring segments of the application servers of the relevant systems. This is done using collection jobs that are automatically scheduled during the configuration of the CPH. Note that the RFC connections to these systems must be correctly configured (see Registering SAP NetWeaver Components and Hosts in CEN).
The performance values of the relevant systems are automatically written to the CPH by agents; with this setting, the CPH does not schedule the jobs and also does not check whether the performance values exist in the CPH. For this setting, CCMS agents must be installed on the systems (agent push).
This method combines both of the above methods. In this case, the CPH only reads the data if the required performance values do not exist in the CPH (that is, by default they are delivered by a CCMS agent).
Reorganization
The reorganization of the CPH means the aggregation of performance values from a higher to a lower temporal granularity and the following deletion of the data with the higher granularity. The aggregation of the data is performed only immediately before its deletion to avoid inflating the CPH with redundant data.
When which data is deleted depends on the settings in the associated collection and reorganization schema. The reorganization is performed by the job SAP_CCMS_CPH_REORG, which is scheduled once a week by default. This job is automatically scheduled when the CPH collects data for the first time; that is, if at least one MTE class is assigned a valid collection and reorganization schema.
If the collection and reorganization schema contains settings that are contradictory (for example, if you want to collect monthly aggregates, but have selected a retention period of less than 31 days for the daily aggregates), the CPH automatically corrects these settings.
There are three jobs that write the performance values to the CPH if you have chosen the Central Data Collection or the Automatic setting:
Job | Description | Period |
---|---|---|
SAP_CCMS_CPH_MINCOLL |
Collection of minute values |
13 minutes |
SAP_CCMS_CPH_QTRCOLL |
Collection of quarter hour values |
110 minutes |
SAP_CCMS_CPH_HRCOLL |
Collection of hour values |
10 hours |
Minute values are stored in the monitoring segment for 30 minutes, quarter hour values for four hours, and hour values for 24 hours. The periods of the three jobs are therefore set so that no data is lost even if one execution fails.
You can display the scheduling status of the collection jobs by choosing, in transaction RZ21, Technical Infrastructure → Central Perf.History → Background Jobs.
The Scheduling Jobs for the Central Performance History screen appears, on which the system displays the following information for each collection job and the reorganization job:
If you call this screen and the above jobs are not scheduled, the system asks whether the jobs should be scheduled (see Activating the Central Performance History).
Once you have assigned valid collection and reorganization schemata to the desired MTE classes, the collection and reorganization of the data in the CPH is performed automatically. Therefore, you do not need to make additional settings.
However, the reorganization job SAP_CCMS_CPH_REORG has a relatively long repetition period of a week. If you collect, for example, minute values, and want to retain these for a week, the data is effectively stored for between one and two weeks ‑ this impreciseness (and therefore also the additional storage required due to the impreciseness) would be drastically reduced with a repetition period of a day.
Note, however, that depending on the size of the CPH, the SAP_CCMS_CPH_REORG job can cause significant workload and should therefore only be executed as often as is required to limit the size of the CPH.
For information about how you can change the periods of the data collection and reorganization jobs, see Changing Extended Settings of the Central Performance History.
Central Performance History of the Monitoring Architecture start page