Intel 170 Servers, AS/400 RISC Server IPL Performance Considerations, IPL Test Description

Chapter 16 IPL Performance

Performance information for Initial Program Load (IPL) is included in this section.

The primary focus of this section is to present observations from IPL tests on different System i models. The data for both normal and abnormal IPLs are broken down into phases, making it easier to see the detail. For information on previous models see a prior Performance Capabilities Reference.

NOTE: The information that follows is based on performance measurements and analysis done in the Server Group Division laboratory. Actual performance may vary significantly from these tests.

16.1 IPL Performance Considerations

The wide variety of hardware configurations and software environments available make it difficult to characterize a 'typical' IPL environment and predict the results. The following section provides a simple description of the IPL tests.

16.2 IPL Test Description

Normal IPL

yPower On IPL (cold start after managed system was powered down completely)

yFor a normal IPL, benchmark time is measured from power-on until the System i server console sign-on screen is available.

Abnormal IPL

ySystem abnormally terminated causing recovery processing to be done during the IPL. The amount of processing is determined by the system activities at the time the system terminates.

yFor an abnormal IPL, the benchmark consists of bringing up a database workload and letting it run until the desired number of jobs are running on the system. Once the workload is stabilized, the system is forced to terminate, forcing a mainstore dump (MSD). The dump is then copied to DASD via the Auto Copy function. The Auto Copy function is enabled through System Service Tools (SST). The System i partition is set to normal so that once the dump is copied, the system completes the remaining IPL with no user intervention. Benchmark time is measured from the time the system is forced to terminate, to when the System i server console sign on screen is available.

ySettings: on the CHGIPLA command the parameter, HDWDIAG, set to (*MIN). All physical files are explicitly journaled. Also logical files are journaled using SMAPP (System Managed Access Path Protection) by using the EDTRCYAP command set to *MIN.

NOTE: Due to some longer starting tasks ( like TCP/IP ), all workstations may not be up and ready at the same time as the console workstation displays a sign-on screen.

IBM i 6.1 Performance Capabilities Reference - January/April/October 2008
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