This chapter includes:
The instrumented kernel emits trace events when:
In addition, all events include the scheduler partition ID and its budget. You can use traceprinter to display the contents of the trace file. You can also use the QNX IDE to parse and display a trace file.
You can—and should—use the System Profiler tool from the QNX IDE to check your system's latencies. For more information about using this tool and the IDE, see the IDE User's Guide.
The easiest method to test a system that uses the thread scheduler is from the command line.
Be sure to test your system in a fully loaded state, because that's where problems are likely to occur. Create a program that consumes resources by looping forever, run it in each partition, and then do the following:
You can use adaptive partitioning to make it easier to debug an embedded system by providing emergency access to it:
In either case, if you don't need to use this partition, the thread scheduler allocates its budget among the other partitions. This provides you with emergency access to the system without compromising performance.
A different approach is to create a separate partition in which to run any questionable applications; if they run wild, the rest of the system should continue to work normally.