Desktop Client: Simulation End Time is over simulation clock limit. Simulation will end at the clock limit.

This article applies to iGrafx Process and iGrafx Process for Six Sigma Client tools

When you check your model for simulation or attempt to run simulation in iGrafx, you may receive errors similar to the following:

    Error: myfile.igx - DefaultScenario:  Generator 'Generator1' must have a valid end-of-generation condition when Simulation End Time is not set.
    Error: myfile.igx - DefaultScenario:  No valid and active generator to start simulation.

OR

    Error: myfile.igx - DefaultScenario:  The simulation stopped because all transactions are waiting for resources that will never become available.

These messages may have various causes. One possible cause can be related to the simulation clock limitations built into iGrafx. One way to determine this is that in some cases you may receive an initial warning message that explains the errors above; something like the following:

    Warning: myfile.igx - DefaultScenario:  Simulation End Time is over simulation clock limit. Simulation will end at the clock limit.

When you receive the first error about no Simulation End Time being set, and you have set a custom end time (vs. using Transactions Complete), or you receive the error about resources and are not using resources or constrained resources, then it's possible that you are running into the simulation clock limit in iGrafx.

There are limits to the amount of time you may simulate in iGrafx. The limits, for the two primary simulation modes, are:

Under calendar mode:

The dates and times that iGrafx can simulate starts at Midnight (0:00) January 1, 1970 and ends at 3:14 AM January 19, 2038. The clock range is 2,147,483,647,000,000 Microseconds. There are two ways to start simulation in Calendar mode:

1. If Simulation starts By Date, simulation clock ends at 3:14 AM January 19, 2038 (about 69 years).
2. If Simulation starts By Weekday, the first weekday in 1970, starting at January 1, that matches that day is used, and the clock range is about 69 years. For example, if the starting date is Thursday, simulation starts on January 1, 1970. If the starting date is Monday, simulation starts on January, 5, 1970. Either way, simulation will only run to 2038.

So if you start a simulation in Calendar mode at a date that will cause the simulator to try to simulate dates beyond 3:14 AM on January 19, 2038, you may receive the error messages above.

Under Compressed mode:

The simulation clock starts from 0 and can run to 4,503,599,627,370,495 microseconds (about 592 years, using the default time conversion of 8 hours/day, and 22 days/month).

What to do when you reach the simulation clock (or date) limit:

You may use one of the following alternate methods to keep your simulation within the clock/date limit for iGrafx:

1. Start simulation at a date that will not cause iGrafx to simulate past the simulation clock (date) limit. For example, if you are running a simulation for 30 years, then start your simulation before June 25, 2008 at 3:14:07 AM. [Note: 30 years with default time conversion settings works out to 360 months at 30 days each, which is 10800 days. So you can start simulation later than Jan. 19, 2008 if you use 30 years for you simulation end time, because you'll run for 10,800 days and not reach the clock limit. If you ran for 10950 days, which is 30 years at 365 days each, you would have to start simulation sooner.]
2. Change the simulation end to stop sooner (e.g. before 2038) and run for less simulated time.
3. Change the generator to stop at a point before 2038 (e.g. before Jan. 19, 2038 at 3:14:07 AM).
4. Use compressed mode (if feasible) to simulate; ensuring you run for less than about 592 years, or about 1250999 hours.