ModelSim SE User's Manual - Electrical and Computer Engineering

Interpreting profiler data
Interpreting profiler data UM-323
The utility of the data supplied by the profiler depends in large part on how your code is
written. In cases where a single model or instance consumes a high percentage of
simulation time or requires a high percentage of memory, the statistical sampling profiler
or the memory allocation profiler quickly identifies that object, allowing you to implement
a change that runs faster or requires less memory.
More commonly, simulation time or memory allocation will be spread among a handful of
modules or entities – for example, 30% of simulation time split between models X, Y, and
Z; or 20% of memory allocation going to models A, B, C and D. In such situations, careful
examination and improvement of each model may result in overall speed improvement or
more efficient memory allocation.
There are times, however, when the statistical sampling and memory allocation profilers
tell you nothing more than that simulation time or memory allocation is fairly equally
distributed throughout your design. In such situations, the profiler provides little helpful
information and improvement must come from a higher level examination of how the
design can be changed or optimized.
ModelSim SE User’s Manual