In each mode, a test can be run under high or low stress levels. The automatic selection feature ensures that the right stress level is enforced by VTS, regardless of what a loaded session file might specify. If there is a mismatch between the stress level specified in a session file and what VTS harness is setting the stress level to, an information message will be logged in the /var/sunvts/logs/sunvts.info file. This automatic forcing of stress level is done only in the System Exerciser mode of testing.
The main rationale of this feature is to prevent test failures caused due to resource exhaustion. The amount of memory in a system is an important factor in setting low or high test levels. If the system has a small memory configuration, the default stress level is set to low in each of the modes. A larger memory configuration results in a default stress level, which is set to high.
The software considers a system to be a small memory configuration if the configured system memory is less than 120 MB, multiplied by the number of CPUs.