Relative performance factor of the CPU (RPF)

In the BS2000 world the performance of a server is expressed in terms of its RPF (Relative Performance Factor). The RPF value indicates the performance capability of the CPUs under a realistic load.

The RPF is determined by measuring with two benchmark loads. An OLTP load (TP benchmark with UTM and SESAM/SQL applications) and a batch load (SKBB benchmark with COBOL programs).

A performance value is obtained for batch mode (RPF_SKBB using jobs per CPU second as the unit of measurement) and TP mode (RPF_TP using transactions per CPU second as the unit of measurement).

The result for TP mode accounts for 75% and the result for batch mode for 25% of the overall RPF value.

Here are some examples of the calculation of the RPF value (the measured values are compared with the values measured for the reference machine C40-F (RPF=1)):

Model	RPFSKBB (RPF value with SKBB benchmark)	RPFTP (RPF value with TP benchmark)	RPFtotal (weighted mean from RPFSKBB and RPFTP)
C40-F	1	1	1
SE310-10R	80	80	80
SE310-10	240	240	240
SE310-20	460	420	430
SE710-10D	860	550	630
SE710-20D	1,690	1,060	1,220
SE710-70	5,010	3,130	3,600
SE710-100	6,560	3,680	4,400

Table 1: Examples for the RPF value

It is not ideal to express the performance behavior of a server in a single figure. As you can see from the table above, the performance depends to a certain extent on the application profile.

Due to the particular architecture and the load-dependent efficiency of the CISC firmware (see "Special features for x86 servers"), the performance of x86 servers is more heavily dependent on the application profile, resulting in a wider performance bandwidth.