  Several approaches have been introduced in the last few years to tackle the
problem of interpreting model-based performance analysis results and
translating them into architectural feedback. Typically the interpretation can
take place by browsing either the software model or the performance model. In
this paper, we compare two approaches that we have recently introduced for this
goal: one based on the detection and solution of performance antipatterns, and
another one based on bidirectional model transformations between software and
performance models. We apply both approaches to the same example in order to
illustrate the differences in the obtained performance results. Thereafter, we
raise the level of abstraction and we discuss the pros and cons of working on
the software side and on the performance side.
