jprofiler cannot be instrumented due to excessive method size

Question

I see following warning in jprofiler run

[warning]Filtered calls in <method name>
cannot be instrumented due to excessive method size.
If needed, please switch to sampling or remove appropriate filters.

The jprofiler version is old 4.2. The method is not that large ~500 lines, just populating some maps.

I would like to know the possible reason for the error.

Answer 1

This happens if the maximum size limit for the method bytecode would be exceeded by adding the instrumentation. See

Maximum size of a method in java?

Adding a filter for the class reduces this problem. In more recent versions of JProfiler you can also add the method to the list of ignored methods then it will not be instrumented at all. And, as the message says, this is not a problem when you use sampling instead of instrumentation.