Measuring System Traffic

As on any road that supports a lot of traffic, bottlenecks can occur in your system. On a highway, cars can be counted with a cable strung across the road, that causes a counter to be incremented each time a car drives over it.

You can use a similar method to measure service traffic. For example, when a server is started (that is, when tpsvrinit() is invoked), you can initialize a global counter and record a starting time. Subsequently, each time a particular service is called, the counter is incremented. When the server is shut down (through the tpsvrdone() function), the final count and the ending time are recorded. This mechanism allows you to determine how busy a particular service is over a specified period of time.

In the BEA Tuxedo system, bottlenecks can originate from problematic data flow patterns. The quickest way to detect bottlenecks is to measure the amount of time required by relevant services from the client's point of view.

Example of Detecting a System Bottleneck

Client 1 requires 4 seconds to display the results. Calls to time() determine that the tpcall to service A is the culprit with a 3.7-second delay. Service A is monitored at the top and bottom and takes 0.5 seconds. This finding implies that a queue may be clogged, a situation that can be verified by running the pq command in tmadmin.

On the other hand, suppose service A takes 3.2 seconds. The individual parts of service A can be bracketed and measured. Perhaps service A issues a tpcall to service B, which requires 2.8 seconds. Knowing this, you should then be able to isolate queue time or message send blocking time. Once the relevant amount of time has been identified, the application can be retuned to handle the traffic.

Using time(), you can measure the duration of the following:

Detecting Bottlenecks on UNIX Platforms

The UNIX system sar(1) command provides valuable performance information that can be used to find system bottlenecks. You can run sar(1) to do the following:

The following table describes the sar(1) command options.

Note: Some flavors of the UNIX system do not support the sar(1) command, but offer equivalent commands, instead. BSD, for example, offers the iostat(1) command; Sun offers perfmeter(1).

Detecting Bottlenecks on Windows 2000 Platforms

On Windows 2000 platforms, you can use the Performance Monitor to collect system information and detect bottlenecks. To open the Performance Monitor, select the following options from the Start menu:

Start —> Programs —> Administration Tools —> Performance Monitor

See Also