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Hi, I have a few servers and paths in my model. I am trying to queue up my entities in the input buffer of server1 when there are too many entities at server2. I am able to set server2's capacity to 3, but I can't seem to set an inputbuffer capacity to server2. I thought I can set the selection weight on my path to server1 to say math.if(server2.inputbuffer.contents>1,0,1), but that doesn't seem to work. I can't seem to find any SimBits on this either. Any help would be appreciated. Thanks.

Hi! I have this: Configurations are like: Then I have the station's contents being displayed in the External definitions. I can count the new entities entering the station.contents, but they don't visually appear in the queue... What am I doing wrong? Thanks!

Thanks Dave for your example, however, we want to trigger the maintenance based on the failure probability of the machine not based on the pressure value. the failure probability if a function of (x,Y). let say that: Pressure = X(t)= kt, t= processing time, k=constant Temp= Y(t)= sin(t)+6t Failure Pr.= P(X,Y) Po= 0.75. >> threshold if Pr(X,Y)=> 0.75 stop the machine. my first thought was to model those two measures as resources put then I couldn't figure out a way to link that with the reliability logic

I am trying to model a server with several failures, where each failure may have a different explanation and thus, a different pattern. One obvious approach is subclassing a Server and defining additional elements, such as Failure, Timers, etc and modify the processes so that several failures can cause the downtime of the server. However, I do not feel very comfortable with the scalabitliy of this approach. I mean, if a server has three types of failures I will have to add two new Failure elements, 8 timers, 4 corresponding to each Failure and so on. If at some point in time I need to add an additional failure, I would need to do the adding all over again, an so on. I am considering two different approaches for this, but I do not know if these are feasible or if there is a far better approach. Approach 1. I would like to subclass the server and create a Repeat Group property so that the user, by means of adding rows, may characterize as many failures as desired. The thing is, is is possible to modify the processes so that they are general enough to reflect any number of failures (with their corresponding characterization)? Approach 2. I was thinking of creating a new object, let us call it objFailure, which contains definitions and processes to reproduce the behaviour of a failure type. The idea would be that this objFailure has a property which would contain the number of an element within the project, so that when objFailure fails, the corresponding object fails. This way, modelling a server with several types of failures woukd consist in creating that server and as many objFailure as required, which would cause the server to fail as they themselves fail. The issue with this approach is that it may not be that easy to represent interferences among failures. For example, if objFailure1 is a count based event failure and objFailure is a Processing Time based failure, when objFailure1 occurs, the server stops and the time during which is down should not be taken into account by objFailure2. This may very complex to program effectively and efficiently.

You can explore the contents of the Simio Standard Library by subclassing any object. You can do that by clicking on MySimioProject in the navigation window or by right clicking on any library object and selecting Subclass. The file itself is StandardLibrary.spfx and can be found in the MyDocuments\SimioModels folder. You should not change this file as it is automatically (re)generated any time its contents do not match what is expected.

Thanks for the suggestion. It now takes 30 seconds runtime for 1 million ... tokens, I guess that would be. First time I try this low-level approach. I followed your instructions (begin-seize-delay-release-tally). Read the Reference PDF as well. Added a Resource1 though (so there was something to seize?). Can see utilization of Resource1 (seems correct at .8321), but no queueing stats and cannot find any results from that Tally Statistics. Will continue to try. Still, I find it slow. I have a Javasimulation of an M/M/1 that takes only 4 seconds to run 1 million customers (=tokens/entities in Simio). Each customer has to be generated, wait for a resource (seize), delay, release it and ends up in a sink (that tallies). Same computer. The javasim has none of the GUI that Simio has, but then, there's no GUI processing overhead in FastForward/experiment mode. And, the Javasim reports queue and worker statistics (mean, variance). Perhaps Simio is collecting excessive statistics (if so, can it be turned off)? Or is it that I made a mistake by adding a Resource1 (to be seized)?

As you have discovered (and I discussed in my post above), running an experiment puts Simio in its fastest run mode possible. And in this mode it will automatically distribute the replications and scenarios across all of your processors/cores. This alone can provide dramatic speedups. If you have Team Edition, you can actually extend that to use spare processing power in your work group. So if you have 4 quad-processor machines available on your local network, you can run up to 16 simultaneous replications or scenarios. In terms of modeling, the most dramatic improvement you could make is to build your model at a lower level. The model you described is simple to model entirely in a single process with steps: (begin) - Seize - Delay - Release - Tally - (end) with the process triggered by a Timer element and using TallyStatistics elements for any token-related statistics like Time In System. You would not even need to create any entities, it could all be done using tokens which are smaller and faster. The process approach should be many times faster.

Hi, I have made an example model illustrating how to do what you are asking. In the attached model, I have 1 entity that requires a 40 hour delay & a Secondary resource for processing. I have a Day Shift worker and a Night Shift worker, each work 12 hour shifts, and the Entity seizes whichever is availabe from a list upon entering the Server. By default, if a secondary resource is seized, the worker will attempt to finish the current job before going off-shift. This is nice if there is something like 15 or 20 minutes left on a job, but not ideal if there is 28 hours left... What I did was created a process that gets Triggered by the Workers' OffShift Add-On process that Interrupts Processing > Releases the Worker > and Transfers the Entity back into the Server Object - which will then start the whole processing process all over again and seize whatever worker is available. Note that in the Interrupt Step, I set the Interupted Process Action to Resume Delay, and the Save Remaining Process Time property to Record ths remaining processing time to the ModelEntity.ProcessTime State (which is initially assigned to 40 in the Source and then gets updated upon every interrupt) For more examples of Interrupting processes see the SimBits: InterruptibleOperator, InterruptingAcrossMultipleServers, & InterruptingServerWithMultipleCapacity Thanks InterruptingProcessingToSwitchWorkers.spfx

Is there a way to use the same instances of workers and resources within the "top-level" model as well as other sub-models? I want to use submodeling really to just compartmentalize the system model and make it easier to digest (I have a large, complex system). I really think I'll just have one instance of each sub-model within my overall model, so I'd like to share workers and resources among all submodels and "processing" objects (servers, combiners, etc.).

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