Intel 170 Servers, AS/400 RISC Server, 7xx Servers manual Web Server and WebSphere Performance

Chapter 6. Web Server and WebSphere Performance

This section discusses System i performance information in Web serving and WebSphere environments. Specific products that are discussed include: HTTP Server (powered by Apache) (in section 6.1), PHP - Zend Core for i (6.2), WebSphere Application Server and WebSphere Application Server - Express (6.3), Web Facing (6.4), Host Access Transformation Services (6.5), System Application Server Instance (6.6), WebSphere Portal Server (6.7), WebSphere Commerce (6.8), WebSphere Commerce Payments (6.9), and Connect for iSeries (6.10).

The primary focus of this section will be to discuss the performance characteristics of the System i platform as a server in a Web environment, provide capacity planning information, and recommend actions to help achieve high performance. Having a high-performance network infrastructure is very important for Web environments; please refer to Chapter 5, “Communications Performance” for related information and tuning tips.

Web Overview: There are many factors that can impact overall performance (e.g., end-user response time, throughput) in the complex Web environment, some of which are listed below:

1) Web Browser or client

yprocessing speed of the client system

yperformance characteristics and configuration of the Web browser

yclient application performance characteristics

2)Network

yspeed of the communications links

ycapacity and caching characteristics of any proxy servers

ythe responsiveness of any other related remote servers (e.g., payment gateways)

ycongestion of network resources

3)System i Web Server and Applications

ySystem i processor capacity (indicated by the CPW value)

yutilization of key System i server resources (CPU, IOP, memory, disk)

yWeb server performance characteristics

yapplication (e.g., CGI, servlet) performance characteristics

Comparing traditional communications to Web-based transactions: For commercial applications, data accesses across the Internet differs distinctly from accesses across 'traditional' communications networks. The additional resources to support Internet transactions by the CPU, IOP, and line are significant and must be considered in capacity planning. Typically, in a traditional network:

ythere is a request and response (between client and server)

yconnections/sessions are maintained between transactions

ynetworks are well-understood and tuned

Typically for Web transactions, there may be a dozen or more line transmissions per transaction:

ya connection is established/closed for each transaction

ythere is a request and response (between client and server)

yone user transaction may contain many separate Internet transactions

ysecure transactions are more frequent and consume more resource

ywith the Internet, the network may not be well-understood (route, components, performance)

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