(I have also posted this question at math.stackexchange.com because I'm not sure where it should belong.)
I have a system with the following inputs:
Set of work items to be completed. These are variable sized. They do not have to be completed in any particular order.
Historical data as to how long work items have taken to complete in the past. However, past performance is no guarantee of future success! That is, once we come to actually execute a work item, we may find that it takes longer or shorter than it has previously.
There can be work items that I have never seen before and hence have no historical data about.
Work items further have a "classification" of "parallel" or "serial".
Set of "agents" which are capable of picking up a work item and working on it. The number of agents is fixed and known in advance. An agent can only work on one work item at a time.
Set of "servers" against which the agents execute work items. Servers have different capabilities. Specifically, they are capable of handling different numbers of agents simultaneously.
Rules:
If a server is being using to execute a "serial" work item, it cannot simultaneously be used to execute any other work item.
Provided a server isn't being used to execute any "serial" work items, it can simultaneously handle as many agents as it is capable of, all executing "parallel" work items.
There are a handful of work items which must be executed against a specific server (although any agent can do that). These work items are "parallel", if that matters. (It may be easier to ignore this rule for now!)
Requirement:
Given the inputs and rules above, I need to execute the set of work items "as quickly as possible". Since we cannot know how long a work item will take until it is complete, we cannot possibly hope to derive a perfect solution up front (I suppose), so "as quickly as possible" means not manifestly doing something stupid like just using one agent to execute each work item one by one!
Historically, I've had a very simple round-robin algorithm and simply sorted the work items by descending historical duration such that the longest running work items get scheduled sooner and, hopefully, at the end of the cycle I'm able to keep all agents and servers reasonably well loaded with short-duration work items. This has resulted in a pretty good "square" shape to the utilization graph with no long tail of long-duration work items hanging around at the end of the cycle.
This historical algorithm, however, has required me to pre-configure the number of agents and servers and pre-allocate work items to "pools" and assign pools to servers, and lots of other horrible stuff. I now need to support a dynamic number of agents and servers without having to reconfigure things. (Note that the number of servers will be fixed during a cycle - that is, the number will only change between cycles - but the number of agents may increase or decrease in the middle of the cycle.)
Once all work items are complete, we record how long each work item took to feed in to the next cycle and start again from the beginning!
Related
I am a PO leading a small development team for enhancements to our PeopleSoft Campus Solutions application for a Medical School.
We are using the Sprint functionality in ADO to assign stories from our backlog to the Sprint, create the relevant tasks for each story (mainly development, testing, deployment) and assign the tasks to resources who, in turn, provide effort values (original estimate, remaining, completed). We also make sure our capacity is properly set, with resources OOO time and school holidays configured to get an accurate team and resource capacity. The team updates their effort numbers daily to ensure we are tracking burndown.
While we always start the Sprint with the remaining work hours under team capacity (and the same at the resource level), we have historically left alot of remaining work on the table at the end of the Sprint.
My leadership wants to answer the question "Why was the work left on the table?". Of course, there could be MANY reasons, we underestimated the effort, we were blocked on a task (for example, we can't start the testing task until the development is done), the resource didn't actually have the calculated capacity due to being pulled into other meetings or initiatives, or (and I don't think this is the case) people were just plain lazy.
What reports/analytics can I leverage to help answer this question? Even just seeing a list of remaining tasks per resource with remaining task effort and with a total amount of work remaining per resource overall would be helpful, but I can't seem to find anything.
Any suggestions or guidance is appreciated!
You can use Queries to find the remaining tasks(add column option->Remaining Work) and save the query into Shared Queries.
There is a query results widget in dashboard to display the query in Shared Queries. Do not forget to add Remaining Working in widget.
Remaining Work:
You could refer to the document: Adjust work to fit sprint capacity
I am trying to simulate a manufacturing assembly process, where material items are processed following an unique line. In the quality control stations, when a failure is detected, the object is sent to the repair area (by a truckpallet) and, when it is repaired, the same resource takes it and puts it at the start of the line. Until this point, I already programmed it.
The problem is the following: when it is a repaired object, is has to follow the same conveyor but with no stops in the stations. The object must enter a station and leave it, with no delays (as the works related with the stations have already been made).
I thought the best would be to consider the difference (repaired vs. not repaired) in the Agent, but then I can't work with it in the Main agent... I have also tried alternative solutions, for example defining variables in each station 1 and consider that in the stations delays and in the following station:
triangular( 109.1*delay_bec, delaytime_bec*delay_bec, 307.6*delay_bec)
Actions - in finished process:
if(delay_bec==0){
delay_headers=0;
delay_bec=1;}
But nothing worked... Any help?
I thought the best would be to consider the difference (repaired vs. not repaired) in the Agent, but then I can't work with it in the Main agent...
This is actually the correct approach. You need to create a custom agent type, give in a boolean variable isRepaired (or similar) and then in the delay you can dynamically adjust the duration using that characteristic:
agent.isRepaired ? 0. : 100
This will delay normal agents by 100 time units and repaired agents not at all.
Obviously, you must make sure that the agents flowing through the flow blocks are of your custom agent type (see the help how to do that)
I am modeling ticket system with various SLA. The model must contain several service blocks with different reaction time ( from 2 to 32 hours). In the service block only working hours should be taken into account. So in the service block timeout should stop when non-workong hours and on the weekend. Could you please kindly tell me how i can realize it?
Thank you very much in advance!
I can think of two answers, one simplified but works in many cases, the other more advanced and probably more accurate:
Simplified approach: I would set the model in hours and keep everything running as is without any stop. So, at the end of the simulation, if the total time is 100 hours and you know that you have 8 hours/day with 5 days/week, then you'd know the total duration is 2.5 weeks. Of course, this might have limitations or might become more complex later on if you want day-specific actions (e.g. you want to differentiate between Monday, Tuesday, etc.)
Advanced more accurate approach: Create resources whose capacities are defined by schedule and assigned them to your services. Create a schedule and specify the working hours in that schedule. Check the below link to learn more about schedules. I call this the more advanced approach because you need to make sure the schedule is defined correctly and make sure all elements in the model are properly controlled (e.g. non-service blocks such as source, delays, etc.).
https://help.anylogic.com/topic/com.anylogic.help/html/data/schedule.html?resultof=%22%73%63%68%65%64%75%6c%65%73%22%20%22%73%63%68%65%64%75%6c%22%20
I personally would use the first approach if the model is rather simple and modeling working hours is enough for analysis. Otherwise, I'd go for option 2.
Finally, another option I'd like to highlight is the "suspend/resume" functions. I am only adding this because you asked "how to stop timeout". So these functions specifically stop and resume timeout. But you'll need to define the times at which they are executed (through an event for example).
Basically I've got a Service which can work with two alternatives of ResourceSets. Let's say, the Service would optimally work with one Doctor and one Nurse, but it is also possible to work with only one Doctor if a Nurse isn't available.
Now, assuming the Doctor works slower without a Nurse, the Service's delay time must depend upon the resourceSet being employed at the moment (Doctor+Nurse or Doctor). Any idea how can I program this?
You should also have in mind that my model has various Services in parallel working in the same way, it's not just only one Service line.
Thanks!
You're using Services but, to me, using the combination of Seize, Delay and Release gives you more flexibility.
What I've done is set the resource choice according to the image bellow:
It is important to have the nurses prior to the doctors in the first set (for some reason anylogic would opt for using only the doctor if otherwise - even with a nurse available).
Than, I would write this code:
Which means that if the agent was only able to seize one resource it will take longer (15 is just a random value).
In the delay block, I would set the processing time to agent.processTime
The topology I'm using is this:
Obviously this is a workaround and will not work for every case. You can always change the conditions you verify. I couldn't find a way to check which resource set was picked by the seize operation. If you're in a hurry this will do the trick.
Hope that helps,
Luís
I have a real-time workflow for creating unique numbers. This workflow get a numeric field from my custom entity, increase it by 1, and update it for next use.
I want to run this workflow on multiple records.
Running on-demand mode, it works fine,and I have true and unique numbers, but for "Record is Created" mode, it dose not work fine and get repeated numbers.
What I have to do?
This approach wont work, when the workflow runs on demand its running multi-threaded, e.g. two users create two records, two instances of the workflow start. As there is no locking mechanism you end up with duplicated numbers.
I'm guessing this isn't happening when running on demand because you are running as a single user.
You will need to implement a custom auto number approach, such as Auto Number for DynamicsCRM.
Disclaimer: I work for Gap Consulting who produce the tool linked above.