ated process, there is no command to limit the process instance creations to a certain number (the command Define-Max-Instance limits the number of instances at a certain moment, but not the successive number of instances created: for example, if you use Define-Max-Instance procl 2, the loop 'process proc2 creates an instance of procl, procl stops (dies)' can be simulated 100 times, triggering the creation of 100 instances). However, it seems that the Validator avoids creating 100 different global states in such a scenario. 4. Reduce the number of instances of entities (block types etc.), and the number of repetitions such as retries to the minimum required for simulation. 5. Use the command Define-Variable-Mode to remove temporary variables (such as a variable receiving the input parameter of a signal, provided the value is not used outside the transition) or variables not influencing the behavior from the global states. This reduces the number of global states. 6. Limit the number of external signals and the number of test values they carry in their parameters. Try to simulate separately independent features. 7. Replace the transmission of external signals by one or several test processes representing external entities (such as a layer above a protocol): the behavior of such test stubs will be more realistic than external signals, generally reducing the number of global states. 8. Reduce the depth limit of the exploration, for example, to 1000 (the default limit is 100, but this is too small in general). In this case, a part of the states graph is not explored. 7.6.2.2 ObjectGeode Simulator Lets suppose we use the exhaustive modes (breadth, depth, liveness). 1. Select Edit > Configuration and set Reasonable environment to on and Loose time progres- sion to off. 264 Validation of Communications Systems with SDL 2. Enter the command define verify_stats true to see the number of states for each process and each queue. Run again the simulation, and after one minute interrupt it to see which input queue must be limi