Components of the persistent data store
The persistent data store consists of a set of components used for writing and retrieving historical data.
Important: The content in this section was
created for and applies to the original persistent data store, referred to as PDS V1. A new PDS
version (referred to as PDS V2) now exists. PDS V1 will eventually be deprecated.
- KPDMANE
- KPDMANE is the primary executable program. It is a server for other applications running in the same address space. This program is designed to run inside the TMS:Engine address space as a separate subtask. Although it is capable of running inside the TMS:Engine, the program does not make any use of TMS:Engine services. This is because the KPDMAIN program is also used in other utility programs that are intended to run in batch mode. KPDMANE is the program that eventually starts the maintenance task when it does a switch and determines that no empty data sets are available.
- KPDUTIL
- This program is used primarily to initialize one or more data sets for persistent data store use. The program attaches a subtask and starts the KPDMANE program in it. The DD statements used when this program is run dictate what control files are executed by the KPDMANE program.
- KPDARCH
- This client program pulls data from the specified data set and writes it out to a flat file. The program attaches a subtask and starts up the KPDMANE program in it. The output data is still in an internal format, with index information excluded.
- KPDREST
- This client program reads data created by the KPDARCH program, inserts it into a data set in the correct format for use by the persistent data store, and rebuilds the index information. The program attaches a subtask and starts the KPDMANE program in it.
- KPDXTRA
- This client program pulls data from a data set and writes it to one or more flat files, with all column data converted to EBCDIC and separated by tabs. This extracted data can be loaded into a database management system or into spreadsheet programs such as Excel. The program attaches a subtask and starts the KPDMANE program in it.
- KPDDSCO
- This program communicates with the started task that is running the persistent data store and sends it commands.
The typical command is
RESUME, which tells the persistent data store that it can resume using a data set. The program can use two forms of communication:- SNA protocol to connect to the monitoring server and submit command requests.
- SVC 34 to issue a modify command to the started task.