Both adaptive and perfective maintenance activities decrease in a dynamic business environment.

Lecture 18 – system maintenance

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Types of maintenance – maintenance tasks

Four types of maintenance

Corrective – performed to fix errors

Adaptive – adds new capability & enhancements

Perfective – improves efficiency

Preventive – reduces possibility of system failure

Some analysts use term maintenance to only describe corrective maintenance, but maintenance really is one of the four types listed above

Costs during maintenance

Operational costs: items such as supplies, equipment rental, & software leases. Lower area of following diagram represents fixed operational costs, and upper area represents maintenance expenses

Maintenance expenses vary widely during system’s operational life & include spending to support maintenance activities, which include:

Changing programs, procedures, or documentation to ensure correct system performance

Adapting the system to changing requirements

Making system operate more efficiently

Total Cost of operating a system

The total cost of operating an information system includes operational and maintenance costs. Operational costs (green) are relatively constant, while maintenance costs (purple) vary over time.

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Lifetime maintenance expenses of a system

Usually high when a system is implemented. Why?

Because problems must be detected, investigated, & resolved by what is known as corrective maintenance

Once system becomes stable, costs remain low. Why?

Involve minor adaptive maintenance

Eventually, both adaptive & perfective maintenance activities increase in a dynamic business environment

Near end of system’s useful life, costs go up again. Why?

Adaptive and corrective expenses increase rapidly, but perfective maintenance decreases when it becomes clear that the organization is going to replace the system

Type depends on the system & its age

corrective

Corrects errors in an operational system

Best maintenance approach is scaled-down version of the SDLC, where investigation, analysis, design, and testing are performed before implementing a solution

Any maintenance work that could affect entire system must be performed on a test environment & then migrated to operational systems

Most orgs have standard procedures for minor errors, such as an incorrect report title

Typical – user submits a systems request that is evaluated, prioritized, & scheduled by sys admin or sys review committee

If approved, maintenance team designs, tests, documents, & implements a solution

Corrective – worst case scenario

Is system failure

If an emergency occurs, maintenance team bypasses initial steps & tries to correct problem immediately.

May require a patch

Meanwhile, a written systems request is prepared by a user or member of IT department & added to maintenance log

When system is operational again, maintenance team determines the cause, analyzes problem, and designs permanent solution

Levels of response

adaptive

Adds enhancements to an operational system & makes the system easier to use

Enhancement is a new feature or capability

Need for this usually arises from business environment changes such as new products or services, new manufacturing technology, or support for a new web-based operation (brick-and-mortar migrating some sales online)

Procedure for minor adaptive maintenance is same as for routine corrective

User submits systems request that is evaluated & prioritized by systems review committee

Maintenance team then analyzes, tests, and implements the enhancement

perfective

Involves changing an operational system to make it more efficient, reliable, or maintainable

Requests for corrective and adaptive normally come from users – IT department usually initiates perfective maintenance

During system operation, changes in user activity or data patterns can cause a decline in efficiency, & perfective maintenance might be needed to restore performance

Can also improve system reliability – input problems might cause a program to terminate abnormally. By modifying data entry process, errors can be highlighted and users notified that they must enter proper data

When system is easier to maintain, support is less costly & less risky

perfective

Many organizations don’t perform perfective maintenance often enough

Companies with limited resources often consider new systems development, adaptive maintenance, and corrective maintenance more important than perfective maintenance

Managers & users constantly requests new projects, so few resources are available for perfective maintenance

Perfective maintenance can be performed as part of another project

It’s usually cost effective in the middle of a system’s life

Software reengineering – uses analytical techniques to identity potential quality & performance requirements in a system.

preventive

To avoid problems, preventive maintenance is performed

Requires analysis of areas where trouble is likely to occur

Often results in increased user satisfaction

Competes for IT resources along with other projects and sometimes doesn’t receive high priority it deserves

Examples of each

The maintenance team

What it requires

Effective Management

Quality Assurance

Cost Control

To achieve these goals, companies use various strategies

A maintenance team

A maintenance management program

A configuration management process

A maintenance release schedule

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Who is in it

System administrator

Administrator should have solid technical experience, & experience in troubleshooting & configuring operating systems

One or more systems analysts

Analysts need strong IT background, solid analytical abilities, good communication skills, and overall understanding of business operations

Programmers

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System administrator

Manages computer & network systems

Must:

Work well under pressure

Have good organizational & communication skills

Be able to understand & resolve complex issues in a limited time frame

Primary responsibility for operation, configuration, & security of systems

Responsible for routine maintenance, usually authorized to take preventive action to avoid an immediate emergency, such as a server crash or network outage

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Systems analyst

Are skilled “detectives” who investigate & rapidly locate the source of a problem by using analysis & synthesis skills

Analysis means examining the whole in order to learn about the individual elements

Synthesis involves studying the parts to understand overall system

Analyst must have

Strong technical skills

Good grasp of business operations and functions

Effective interpersonal & communications skills

Be creative, energetic, & eager for learning new systems and techniques

Programmers

In a small organization, a programmer may also be required to perform analysis functions

In larger firms, work tends to be more specialized

Applications programmers

Database programmers

People who perform both programming & analysis functions are often called programmer/analysts

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Organizational issues

Division of labor

Systems analysts and programmers are often divided into two groups

One performs new system development

The other handles system maintenance

Other organizations use a more flexible approach

Assign IT staff members to projects as they occur

So some personnel would be performing both new system development & maintenance once the system has been implemented

Depends on the organization

How analysts feel

Maintenance is less interesting & less creative than developing new systems

Might find it challenging to troubleshoot & support someone else’s work that might have been poorly documented & organized

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Job rotation

Some orgs that have separate maintenance & new systems groups rotate them from one assignment to the other

When analysts learn different skills, org is more versatile & people can shift to meet changing business needs

Systems analysts working on maintenance projects learn why it’s important to design easily maintainable systems

Analysts working on new systems projects get better appreciation of development process & design compromises required to meet business objectives

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Problems with rotation

It increases overhead b/c time is lost when people move from one job to another

When people constantly shift from one role to the other, they have less opportunity to become proficient in either

Newly hired & recently promoted IT staff members are often assigned to maintenance projects b/c their managers believe that the opportunity to study existing systems & documentation is a valuable experience

Another reason – the mini-SDLC used in many maintenance projects is good training from full-scale systems development projects

But for a new systems analyst, maintenance work may be more difficult than systems development, & so it might make sense to assign a new analyst to a development team where experienced analysts can provide training and guidance

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Maintenance requests

Typical process for handling maintenance requests

Steps of handling the request

Initial determination – when user submits maintenance request, sys admin makes initial determination. If request is justifiable & involves a severe problem that requires immediate attention, sys admin at once. If not critical, admin determines whether request can be performed within a preauthorized cost level

Systems review committee – when request exceeds predetermined cost $$ level, sys review committee either approves it & assigns a priority or rejects it

Task completion – sys admin is responsible for assigning maintenance tasks to individuals or a team

User notification – users who initiate maintenance requests expect a prompt response. Even if the work cannot be done immediately, they must be notified

Maintenance releases

Documents and installs changes as a new version

Maintenance release methodology: Retains all noncritical changes and implements them simultaneously

Advantage - All changes are tested together, resulting in fewer versions and lesser expense

Disadvantage - New features of upgrades are available less often

Service packs: Maintenance releases provided by commercial software suppliers

Numbering:

1.0 is initial version of system. Release that includes first set of maintenance changes would be version 1.1

Change from version 1.4 to 1.5 would include minor enhancements

Whole number changes, from 1.0 to 2.0, or 3.4 to 4.0, indicate a significant upgrade