Intel 170 Servers manual ISeries and AS/400 Risc Server Model Performance Behavior, Overview

Chapter 2. iSeries and AS/400 RISC Server Model Performance Behavior

2.1 Overview

iSeries and AS/400 servers are intended for use primarily in client/server or other non-interactive work environments such as batch, business intelligence, network computing etc. 5250-based interactive work can be run on these servers, but with limitations. With iSeries and AS/400 servers, interactive capacity can be increased with the purchase of additional interactive features. Interactive work is defined as any job doing 5250 display device I/O. This includes:

All 5250 sessions	RUMBA/400
Any green screen interface	Screen scrapers
Telnet or 5250 DSPT workstations	Interactive subsystem monitors
5250/HTML workstation gateway	Twinax printer jobs
PC's using 5250 emulation	BSC 3270 emulation
Interactive program debugging	5250 emulation
PC Support/400 work station function

Note that printer work that passes through twinax media is treated as interactive, even though there is no “user interface”. This is true regardless of whether the printer is working in dedicated mode or is printing spool files from an out queue. Printer activity that is routed over a LAN through a PC print controller are not considered to be interactive.

This explanation is different than that found in previous versions of this document. Previous versions indicated that spooled work would not be considered to be interactive and were in error.

As of January 2003, 5250 On-line Transaction Processing (OLTP) replaces the term “interactive” when referencing interactive CPW or interactive capacity. Also new in 2003, when ordering a iSeries server, the customer must choose between a Standard Package and an Enterprise Package in most cases. The Standard Packages comes with zero 5250 CPW and 5250 OLTP workloads are not supported. However, the Standard Package does support a limited 5250 CPW for a system administrator to manage various aspects of the server. Multiple administrative jobs will quickly exceed this capability. The Enterprise Package does not have any limits relative to 5250 OLTP workloads. In other words, 100% of the server capacity is available for 5250 OLTP applications whenever you need it.

5250 OLTP applications can be run after running the WebFacing Tool of IBM WebSphere Development Studio for iSeries and will require no 5250 CPW if on V5R2 and using model 800, 810, 825, 870, or 890 hardware.

2.1.1 Interactive Indicators and Metrics

Prior to V4R5, there were no system metrics that would allow a customer to determine the overall interactive feature capacity utilization. It was difficult for the customer to determine how much of the total interactive capacity he was using and which jobs were consuming interactive capacity. This got much easier with the system enhancements made in V4R5 and V5R1.

Starting with V4R5, two new metrics were added to the data generated by Collection Services to report the system's interactive CPU utilization (ref file QAPMSYSCPU). The first metric (SCIFUS) is the

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