The tables below show some performance data and standard values for BS2000 servers. The recommendations apply for typical TP operation with a normal background load.
Relative Performance Factor RPF and number of CPUs.
Typical main memory configuration.
The actual main memory requirement depends on the load with which the server is operated. TP and dialog loads normally have a significantly greater main memory requirement than batch loads.On x86 servers, the main memory is distributed between BS2000 and Dom0/X2000 (I/O processor). A recommendation for the configuration and distribution of main memory is shown in the relevant tables.
Information on when more main memory than recommended there should be used is provided in section “Special features for x86 servers”.Maximum recommended number of DMS I/O operations.
An IT system is used economically when it is executing a balanced mixture of programs requiring an intensive use of calculation functions and programs requiring an intensive use of I/O functions. The recommended maximum number of DMS I/O operations per second is not an upper limit determined by technical requirements, but guarantees that only a certain proportion of the CPU capacity is used to perform I/O operations. It can be exceeded without problems, provided bottlenecks in the peripherals are avoided.Maximum recommended number of paging I/O operations.
The maximum recommended paging rates specified for transaction mode or interactive mode ensure that only a certain proportion of the CPU capacity is used for paging. To avoid delays through paging (especially in transaction processing mode), you should try to aim for less than the stated values in view of the main memory available.Maximum recommended number of SVCs in TU.
When the maximum number of SVC calls per second is reached, the effort required for the interrupt analysis and termination handling of the system routine (i.e. not the resources used for the system routine itself) amount to approx. 5% of CPU time.