Before You Test

Warning

Before running Rendezvous performance assessment software, read this section carefully.

Test in an Insulated Environment

We strongly recommend that you run all performance tests in a network environment that is insulated from other Rendezvous applications and other network traffic.

Consider these two important benefits of an insulated environment:

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Insulation prevents performance assessment message traffic from disrupting deployed applications.

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Insulation ensures that traffic from other applications does not skew performance measurements.

Testing in a physically isolated network yields the most accurate measurements.

When physical isolation is impractical, you can still obtain valid measurements by insulating tests within unused multicast addresses. However, in this arrangement, rvperfm traffic can still affect the performance of other deployed network applications.

rvd Reliability

Warning

To ensure accurate and efficient testing, it is critical that you first disable the reliable message storage feature of rvd. To disable reliability fordaemons, manually start rvd (or rvrd) with the command line parameter -reliability 0. This zero value instructs rvd not to retain outbound messages in case they are needed for retransmission. For more information, see Reliability and Message Retention Time.

rvperfm attempts to determine the carrying capacity of the network. To do so, it tests whether the network and a set of receivers can absorb a run of messages without missing any packets. The reliable delivery feature of rvd defeats this purpose; it compensates for transient network problems by retaining and retransmitting packets. This behavior is often beneficial in a production environment, but in a performance testing situation it is counterproductive—by compensating for network problems, it delays detection of those problems. This delay falsifies the results of performance testing, and unnecessarily prolongs the testing period.