Smart Vuser allocation (formerly load balancing) balances the load generated by Vusers, distributing the load evenly among the requested load generators. This improves the accuracy of the load test.
Smart Vuser allocation is available in manual scenarios in percentage mode. In this type of scenario, if smart Vuser allocation is enabled, Controller allocates Vusers to each load generator based on the CPU usage of the load generators. Smart Vuser allocation can only determine the allocation of each Vuser before the Vuser is loaded. This means that for smart Vuser allocation to work, the scenario must be set to load Vusers gradually and not all at once.
When a load generator's CPU usage becomes overloaded, Controller receives a message and stops loading Vusers on the overloaded load generator, and automatically distributes them among the other load generators taking part in the scenario. Only where there are no other available load generators in the scenario does Controller stop loading Vusers.
You can monitor the status of a machine's CPU usage using the icons in the Load Generators dialog box (see Load Generators dialog box). When the CPU usage of a load generator becomes problematic, the icon to the left of the load generator name contains a yellow bar. When the machine becomes overloaded, the icon contains a red bar.
Tip: You can monitor a load generator's CPU usage in greater detail using the Controller and Load Generator Resources monitor. For details, see Controller and Load Generator Resources monitor.
Smart Vuser allocation works most efficiently in scenarios with a high number of Vusers.
From version 2022 R2: To enable smart Vuser allocation, in Controller, select Tools > Options > Execution tab and check the Use Smart Vuser allocation (only in percentage mode scenario) checkbox. In earlier versions, load balancing is enabled automatically.
- Smart Vuser allocation and load balancing are not supported for Dockerized load generators.
- In version 2022 R1 and earlier:
- Load balancing is available in manual scenarios in percentage mode, and in goal-oriented scenarios.
- Load balancing is supported for Windows load generators only.