348 Performance Tuning for Content Manager
12.1 Troubleshooting basics
The key to successfully and efficiently resolving performance problems in a
Content Manager system is to have an organized, disciplined process that
focuses on identifying and relieving the system’s performance bottlenecks.
Without an organized process focused on identifying bottlenecks, it is very easy
to spend a lot of time and energy tweaking various parameters, ending up with a
system in a worse state than before with no good record of what was changed
and why. To be successful, you must collect the right data and find the real
bottleneck. You will then be able to address that bottleneck, tune the system, and
improve the performance of your Content Manager system.
Before beginning any full performance troubleshooting process, first ensure that
the database statistics for the Library Server and Resource Manager databases
are up to date. Content Manager is a database application. It depends heavily on
accurate database statistics for optimizing all operations. Updating database
statistics on the Library Server and Resource Manager databases is quick and
easy to do, and often turns out to be the only fix needed.
Performance problems are often caused by changes in the system. The changes
that might affect system performance include:
Hardware changes
Example: Adding new disks or changing hardware configurations
Operating system changes
Example: Installing PTFs or changing parameters
Software changes
Example: Adding fix packs for DB2 and WebSphere, or configuration changes
Application changes
Example: Installing or upgrading new versions and fixes, configuration
changes, installing new modules, or adding new users or new content
Performance tuning
Example: Tuning changes in operating system, network, DB2, WebSphere,
TSM, or the application
Any changes
Is it a performance problem?
When a user complains about a problem or you experience a problem firsthand,
you must first determine the nature of the problem: whether it is a functional
problem or a performance problem. When your hardware, network, or application
does not behave correctly, it is a functional problem (for example, if your Content
Chapter 12. Troubleshooting performance problems 349
Manager application has a memory leak). Sometimes, functional problems lead
to performance problems (an application memory leak eventually slowing down
the overall system performance). In such cases, it is important to determine the
root cause of the problem and fix it rather than focus on tuning your system.
Using the example of application memory leak, you need to address the problem
to the development team and ask them to eliminate the memory leak.
Asking questions
Before jumping into collecting data and analyzing data, you should get as much
detailed information as possible about the problem experienced by users.
Questions to ask users or to research on your own include:
Is this an across-the-board problem, or does it affect only certain operations
or users?
What operations are slow — the time it takes to search for a document or to
display a document, for example?
Can the problem be reproduced by exercising a certain task or sequence of
events?
Is the slow performance intermittent (does it disappear from time to time)?
Does it occur at a certain time of day or in relation to certain tasks?
When did the problem start occurring? Was the situation the same when the
system was first installed or went into production? (Is this a regression or
were the performance objectives never met?) Did anything change on the
system before the problem occurred (such as adding more users or loading
additional legacy content to the system)?
Is this a single-user performance problem or multi-user scalability problem?
If remote users are complaining about document retrieval, do local users
performing the same document retrieval experience the same slowness
(network versus server issue)?
If this is network related, how are the network segments configured (including
bandwidth such as 10 Mbps or 9600 baud)? Are there any routers between
the client and server? Are the objects cached?
What other applications are running on the system, and are those
applications involved in the performance issue?
What is the impact of the performance problem on the users?
After understanding the nature of the problem, we need to find the location of the
bottleneck or what area causes the problem. Several actions can be taken:
Use monitoring tools and programs to check system performance:
Obtain workload metrics to compare with the baseline.

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