An operational profile describes, in a probabilistic way, how
a software is utilized by its users. It makes the testing procedure
more realistic and efficient. We consider a model where the
software is tested sequentially in all of the operations that
it is designed to perform. The stochastic and deterministic
model parameters involving costs and failures all depend on
the operations. In particular, the failure process generated
by each fault is quite general and debugging is not necessarily
perfect. Our aim is to find the optimal testing durations in
all of the operations in order to minimize the total expected
cost. This problem leads to an interesting nonlinear programming
formulation that can be solved using well-known procedures in
convex optimization.