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Thank you very much. I was able to create a new model with two servers and have my entities queue up in the server1's input buffer. Then I tried to do something similar with three servers where I want server1's input buffer to have entities queue up when server3 is busy. I have server2 in between server1 and server3. I set server2's input and output buffers to 0 and set server1 and server2 and paths as described below. Is this correct, to set the in between server's input and output buffers to 0? Everything seems to work as expected and I get a long queue at server1's input buffer. I also used a rate table with many entities going through. An interesting thing I noticed was that if I change server1 and server2 process times to 3 and 2 seconds respectively and leave server3 process time to the default random.triangular(.1,.2,.3) minutes. I also changed a few selection weights. I barely ever get a queue at server1 input buffer, and when I do, the time in queue is very small. I would have expected a significant queue with the rate table I am using. Does this sound correct? I also ended up getting a Simio error that I ended up sending to Simio, subject [sIMIO EXCEPTION REPORT] from mmashaie. This email includes the model. Thanks again. Your help has been great. Maryam

Sure. You can make tightly coupled servers by connecting them with a Connector and having Server1 output buffer capacity and Server 2 input buffer capacity set to 0. But it sounds like you want more loosely coupled servers, so for example you could set: -Server1 Output Buffer is 0 (nothing waits there) -Path2 Capacity is 1 (only 1 can wait there) -Server2 Input Buffer is 1 (only 1 waits there) -Server1 Capacity is 1 (only 1 can be there) So you can have a total of up to 3 entities in or on the way to Server 2. Beyond that Server1 will be blocked and and additional entities will wait in Server1 Input Buffer. (I would have attached a model if you had posted this in an SI folder, but attachments are limited in these public folders.)

Ah shucks Dave. Thanks for the call out. I enjoy using Simio, as it is one of the premier simulation tools, and I would like to see it become the standard "go-to" tool for general simulation purposes. I have a vested interest in steering development towards mining purposes, so at times I am sure that what I was requesting might have been a polar opposite to the direction you intended to take development for general purposes. That being said, out of the massive list of suggestions I have made over the last year, a good portion have been added. I trust Simio will continue to grow and mature, and I hope to play a small part in this happening... even if it is only to throw peanuts from the gallery.

I'm not sure about the answer to your question, although I believe it dynamically creates the times. However, I WAS able to change the factor on the time varying arrival rate... the attached model uses an arrival rate of 60/hour for the first hour, then i change the rate factor to 1/60 so it will have a rate of 1/hour. This drastic difference is immediately noticeable. Is this what you were trying to do? testRateFactors.spfx

I have been running very large experiments that take a few days to run. Murphy's law seems to interfere through either power outages or automatic updates which can cost me a couple of days of computer time. So I found some code using autohotkey and modified it to work great with SIMIO. autohotkey is a free download and easy to use. The below code runs a loop which hits {control S} on the SIMIO window if it is open every 10 minutes. Persistent ;run a loop 100 times saving every ten minutes if your SIMIO file is open. loop, 100 { ;save file every 10 minutes MsgBox, Iteration number is %A_Index%. setTimer, AutoSave, 6000000,on AutoSave: IfWinActive, ;name_of_simio_file_without_spfx_extension Send {Blind}^s return } return

Many times, you are not sure if the port is open between the Simio GUI (client) and the Simio Network License Server. The program in the attached zip will allow you to test whether the port is open. Just unzip the CheckPort.exe from the attached zip file. Then run the program and enter the host and port. If you get a Socket Exception, you cannot connect to the server / port. If you get a message saying "Socket connect to...", the port is open. CheckPort.zip

Assuming you have a property or state named TargetTime, then you could delay each individual entity by "TargetTime-TimeNow". Regardless of the times that individual entities arrive, they will all finish their delays at TargetTime and then move forward together.

Tried free eval version of Csim20, the included console M/M/1 demo. CPU-time reported is 2.5 secs (same computer) for 1M jobs. A bit faster than the Javasim. Csim obviously does book-keeping of all arrival/departure times to show queueing averages, but this can be turned off, which is what I now want to do in SIMIO. Turn on statistics only for specified objects.

I am not surprised by your findings. I would expect an simulation executed entirely in a traditional programming language to be many times faster than a simulation created in a seperate software package. I'm very impressed that Simio managed 30 seconds compared to 4 seconds for your java simulation. The 4 seconds actually looks slow to me!

This is something I have heard others talk about, but never actually got working for myself. Is it possible to reference a file with a dynamic name? I want to write out to a csv file during simulation runs, but the write originates from a submodel. This means that it is called multiple times, meaning that only one of my sub models actually gets to write. What is the easiest way to over come this? And yes, the write must originate from the sub-model.

I see that the EXPERIMENT MODE is 2-4 times faster. I try this (one replication) and it runs slightly faster (109 runtime seconds compared to 115). One CPU ran at 90 %, the other at 10 %. I try to run two replications, now both CPUs run at 100 %. Runtimes are 121 and 124 seconds (wall clock time is about 125 seconds). So, I can see that experiment mode on my dual core CPU halves my waiting time when running experiments. But, each individual simulation is still 110-115 seconds runtime on a dual core CPU that is about 50 % utilized. I assume there is no way to speed up Simio further than this.

Today I had to do a quick and dirty model in Arena. I just thought I would take this opportunity to do a quick post on my findings. By no means is this a comprehensive analysis of the two tools, but I just felt like sharing my opinion of the two. Being the predecessor to Simio, it is natural to compare the two tools, and even after using Arena for the short amount of time I did... the differences were astounding. I will admit that Simio was my first immersion into the world of using corporate modelling tools. It was a tough journey to get to the stage where I felt comfortable using Simio, but looking back... I wonder how I got by using the archaic tools I did. The learning curve to Simio was extremely steep (in my humble opinion that is), and I still don't believe I am anywhere near utilizing 100% of Simio's capabilities. That being said... Simio is a relatively new tool and is still under active development. After launching Arena for the first time, the first thing that struck me was how bland/simple it was. Putting that to one side, I was impressed with how intuitive it was to use. This may be a side effect of using Simio, but barring my inability to find the Connect button for linking the objects together, I simply dragged objects into the process view and linked them up. The objects all had names that made sense (workstation... server... what were you guys thinking? >_>), and ignoring the fact that most of the symbols looked like they were drawn by pre-schoolers... the process of getting a simple model running was child's play. Within 5minutes I had my first working model. (I can tell you that it took a lot longer than that for my first Simio experience) One of the features I would love to see the most in Simio... AVI export. It was right there, and it was easy. Come on Simio! After placing multiples of an object, there was a table at the bottom of the screen with every other object of the same type, allowing you to quickly locate and edit properties of said objects... Simio... adding something like this would immeasurably improve productivity (mine atleast) and increase my levels of sanity after working with large models. Another point to note was that Arena felt very responsive, and while this normally would not be an achievement for a piece of software... Arena did not crash or give cryptic errors. (Simio crashed multiple times during my first 30minute experience with it... and I didn't even know how to do anything more advanced with it at that stage). The last point to make in this section of the post, is how human readable the reports were. My eyes were not assaulted with a million numbers. You could argue this is a bad thing or a good thing, but at the end of the day, some of these reports matched what I typically look for in Simio, and have to waste time trying to get. They were also laid out clearly and concisely. I am sure Arena has a fairly similar learning curve to Simio once you get to the more advanced stuff, but I have got to say that Arena definitly has the edge of many years of polish and tweaking. I am not here though to plug Arena. Let's get to the meat of this post now. The things I saw in my short time using Arena in comparison to Simio, that Simio did better. Even though I feel Simio has a lot more work to do on getting their product to the kind of a level Arena sits at (polish and usability) in terms of: aesthetics, power, time-savings (gained from re-usability of objects in Simio, instead of hard coded processes in Arena), feature base, and on-going development... Simio wins hands down. The benefits of object based models in comparison to process based models are imeasureable, and while some of the more basic features you would expect (or take for granted) in a modelling tool are lacking or missing in Simio, a lot of thought and has gone into the development of this tool. You can really see how Simio is the next generation of tool. I guess the point I am really trying to convey is, Simio rocks. It may be buggy as hell, it may not have every bell and whistle to satisfy my unreasonable demands, and it may not be as smooth or intuitive as Arena, but it is actively developed and a lot of love and care went into its development. I dare say that given time and a bigger/more active community, Simio will truly come into its own. The Arena community may be larger, but it does not appear as if Arena itself is evolving to meet the ever changing demands of the market. I guess it won't be long until the remaining Arena modellers move on and embrace newer technologies like Simio. Sorry for the long post. TLDR: Keep up the good work guys!

In the current version of Simio, there is no fixed relationship between simulated time and real time. The model will run as fast as possible given the contraints of the number of simulation events and related "work" being done. The two other things that most dramatically impact simulation speed are Trace (when trace is on it excuted slower) and Animation (3D animation with a low speed factor runs slower). We have plans to provide an Emulation product for use in training and testing. Before that product is created, we will add the capability for Simio to run in real time or any multiple of real time. Speed Factor can be used to speed or slow the animation. Its main purpose is to improve the quality of an animation by decreasing the factor. This also has the side effect of slowing the animation so you can see certain events more clearly. Conversely, if you increase the speed factor, the animation will run faster, but in doing so, certain events (like movement on a path) might become jumpy or too fast to observe. Fast-Forward can be used to temporarily disable animation to allow the model to execute much fsater. Running an Experiment provides the fastest execution possible. Not only is animation and user interaction turned off, but it will also take full advantage of all processors on a multiprocessor machine, often running 2-4 times faster.

A common way to create object definitions in Simio is by combining other objects, for example combining machines and a robot to define a work cell object. This type of object is called a composed object because we create this object by combining two or more component objects. This object building approach is fully hierarchical, i.e. a composed object can be used as a component object in building higher level objects. A second, more basic method for creating objects in Simio is by defining the logical processes that alter their state in response to events. For example, a machine object might be built by defining the processes that alter the machine state as events occur such as part arrival, tool breakdown, etc. This type of modeling is similar to the process modeling done in traditional modeling systems in use today such as Arena or GPSS. An object that is defined by describing its native processes is called a base object. A base object can in turn be used as a component object for building higher level objects. The final method for building objects in Simio is based on the concept of inheritance. In this case we create an object from an existing object by overriding (i.e. replacing) one or more processes within the object, or adding additional processes to extend its behavior. In other words we start with an object that is almost what we want, and then we modify and extend it as necessary to make it serve our own purpose. For example we might build a specialized drill object from a generalized machine object by adding additional processes to handle the failure and replacement of the drill bit. An object that is built in this way is referred to as a derived object because it is sub-classed from an existing object. Regardless which method is used to create an object, once created it is used in exactly the same way. An object can be instantiated any number of times into a model. You simply select the object of interest and place it (instantiate it) into your model.

Simio is a simulation modeling framework based on intelligent objects. The intelligent objects are built by modelers and then may be reused in multiple modeling projects. Objects can be stored in libraries and easily shared. A beginning modeler may prefer to use pre-built objects from libraries; however the system is designed to make it easy for even beginning modelers to build their own intelligent objects for use in building hierarchical models. An object might be a machine, robot, airplane, customer, doctor, tank, bus, ship, or any other thing that you might encounter in your system. A model is built by combining objects that represent the physical components of the system. A Simio model looks like the real system. The model logic and animation is built as a single step. An object may be animated to reflect the changing state of the object. For example a forklift truck raises and lowers its lift, a robot opens and closes its gripper, and a battle tank turns its turret. The animated model provides a moving picture of the system in operation. Objects are built using the concepts of object orientation. However unlike other object oriented simulation systems, the process of building an object is very simple and completely graphical. There is no need to write programming code to create new objects. The activity of building an object in Simio is identical to the activity of building a model – in fact there is no difference between an object and a model. This concept is referred to as the equivalence principle and is central to the design of Simio. Whenever you build a model it is by definition an object that can be instantiated into another model. For example, if you combine two machines and a robot into a model of a work cell, the work cell model is itself an object that can then be instantiated any number of times into other models. The work cell is an object just like the machines and robot are objects. In Simio there is no way to separate the idea of building a model from the concept of building an object. Every model that is built in Simio is automatically a building block that can be used in building higher level models.