Confusion regarding usage of event.triggered - system-verilog

I'm trying out some code that is supposed to block until moving to a new simulation time step (similar to waiting for sys.tick_start in e).
I tried writing a function that does this:
task wait_triggered();
event e;
`uvm_info("DBG", "Waiting trig", UVM_NONE)
-> e;
$display("e.triggered = ", e.triggered);
wait (!e.triggered);
`uvm_info("DBG", "Wait trig done", UVM_NONE)
endtask
The idea behind it is that I trigger some event, meaning that its triggered field is going to be 1 when control reaches the line with wait(!e.triggered). This line should unblock in the next time slot, when triggered is going to be cleared.
To test this out I added some other thread that consumes simulation time:
fork
wait_triggered();
begin
`uvm_info("DBG", "Doing stuff", UVM_NONE)
#1;
`uvm_info("DBG", "Did stuff", UVM_NONE)
end
join
#1;
$finish(1);
I see the messages Doing stuff and Did stuff, but Wait trig done never comes. The simulation also stops before reaching the finish(1). One simulator told me that this is because no further events have been scheduled.
All simulators exhibit the same behavior, so there must be something I'm missing. Could anyone explain what's going on?

The problem is with wait (!e.triggered); when e.triggered is changing from 1 to zero. It has to change in a region where nothing can be scheduled, so whether it changes at the end of the current time slot, or the beginning of the next time slot is unobservable. So the wait will hang waiting for the end of the current time slot, which never comes.
I think the closest thing to what you are looking for is #1step. This blocks for the smallest simulation precision time step. But I've got to believe there is a better way to code what you want without having to know if time is advancing.

Related

Anylogic: Queue TimeOut blocks flow

I have a pretty simple Anylogic DE model where POs are launched regularly, and a certain amount of material gets to the incoming Queue in one shot (See Sample Picture below). Then the Manufacturing process starts using that material at a regular rate, but I want to check if the material in the queue gets outdated, so I'm using the TimeOut option of that queue, in order to scrap the outdated material (older than 40wks).
The problem is that every time that some material gets scrapped through this Timeout exit, the downstream Manufacturing process "stops" pulling more material, instead of continuing, and it does not get restarted until a new batch of material gets received into the Queue.
What am I doing wrong here? Thanks a lot in advance!!
Kindest regards
Your situation is interesting because there doesn't seem to be anything wrong with what you're doing. So even though what you are doing seems to be correct, I will provide you with a workaround. Instead of the Queue block, use a Wait block. You can assign a timeout and link the timeout port just like you did for the queue (seem image at the end of the answer).
In the On Enter field of the wait block (which I will assume is named Fridge), write the following code:
if( MFG.size() < MFG.capacity ) {
self.free(agent);
}
In the On Enter of MFG block write the following:
if( self.size() < self.capacity && Fridge.size() > 0 ) {
Fridge.free(Fridge.get(0));
}
And finally, in the On Exit of your MFG block write the following:
if( Fridge.size() > 0 ) {
Fridge.free(Fridge.get(0));
}
What we are doing in the above, is we are manually pushing the agents. Each time an agent is processed, the model checks if there is capacity to send more, if yes, a new agent is sent.
I know this is an unpleasant workaround, but it provides you with a solution until AnyLogic support can figure it out.

Is it possible to dynamically update if functions in anylogic?

I'm using a state chart in combination with a schedule in Anylogic (see picture). The output of the schedule is equal to 1 during working hours and 0 otherwise. Now I want the transition from state1 to state2 to happen when the schedule is turning to 1 or is equal to 1(so otherwise wait until the working hours).
I have tried using an if statement
if( main.plannerSchedule()==1 )(<perform action>)
However, by this method, the state transition only happens if the statement is true but doesn't wait for it to become true. Is there a way to constantly update the state transition or is there a "wait until" function that can solve this problem?
Best let the schedule send a message to your statechart when it switches. This assumes that the statechart lives on the same agent type as the schedule. Write this code in the action code box of the schedule:
if (value==1) {
statechart.fireEvent("go to state 2");
}
Obviously, your message transition needs to await the "go to state 2" message.
Note the value keyword. See https://www.benjamin-schumann.com/blog/2016/2/4/the-magic-lightbulb-and-how-it-can-help-your-anylogic-modelling for more info on that

SFC Steps in IEC 61131-3 Programming

So I have a problem where in my SFC it jumps to an inital step but the commands written in the step would not register.
At the end of the SFC a step inputs 5 into A_Status(INT).
The very next transition checks if the value of A_Status is 5.
No problems so far, but after the transition when it jumps to the start of the SFC,
where the first step is supposed to input 0 into A_Status, A_Status stays at 5.
The cycle time of my program is 100ms. I have tried slowing the cycle but it didn't work.
What seems to be the problem here? Maybe the same variable used in such a sequence just doesn't work?
Reply would be greatly appreciated.
You don't mention if you write the values during Entry/Exit or in the SFC step actions. But beware, that on some occasions code from a previous step can be executed later than code in the new step.
Here is a link that explains the call order and why sometimes parts of the code is executed twice:
https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_plc_intro/45035999420423563.html
I've had succes with adding the following code in all the actions to prevent this from happening.
IF STEP_NAME.x THEN // Only execute this while the step is active.
// Insert code here.
END_IF

Health Reporting Stuck

In a simple stateless service I am attempting to report health. As a test I am simply flipping between OK and Warning states on every iteration of my loop in RunAsync (it has a sleep interval of 15secs). The code looks like this:
// report warning on odd iterations
HealthState state = ((++iterations % 2) != 0) ? HealthState.Warning : HealthState.Ok;
HealthInformation health = new HealthInformation("ServiceCode", "Iteration", state);
Partition.ReportInstanceHealth(health);
I am logging the state on each iteration of the loop and the log shows it flipping back and forth. But in the SF Explorer it is stuck on Ok, never switching to Warning (I have a refresh interval of 5secs in SFExplorer).
What am I doing wrong here?
Try specifying HealthInformation.SequenceNumber with an incremental value for every state change.
Looks like health reporting is significantly slower than I would expect. Working on that 15sec interval was not enough time for it to show the alternating health state. Moving to a 30sec interval seems to have resolved it.

Quartz.net tracking and misfiring

I have a few questions regarding quartz.net.
What is it that keeps track of if there has been a missfire situation i Quartz.net?
What happens in the following scenarios:
If a job is run but cannot finnish due to some bug, does that count as a missfire or not?
What happens if i republish the solution, is the tracking reset?
Is there a way to receive information on what the scheduler has done and not been able to do?
I have the following code in my Run method:
IJobDetail dailyUserMailJob = new JobDetailImpl("DailyUserMailJob", null, typeof(Jobs.TestJob));
ITrigger trigger = TriggerBuilder.Create()
.WithIdentity("trigger1", "group1")
.WithCronSchedule("0 0 4 1 * ?", x => x.WithMisfireHandlingInstructionFireAndProceed())
.Build();
this.Scheduler.ScheduleJob(dailyUserMailJob, trigger);
this.Scheduler.Start();
The job is supposed to run the first every month on 4 am.
When testing I have set the system clock so that the jobb is missed for one month. According to the documentation when using WithMisfireHandlingInstructionFireAndProceed the job should be run the first thing that happens, but it dosent. Is there something wrong with the code or could it be some other reason the job is not run when using WithMisfireHandlingInstructionFireAndProceed() ?
If a job is missed, there is logic to bring it back. However, there is a "window" on how far back to go.
<add key="quartz.jobStore.misfireThreshold" value="60000"/>
You can increase this value.
If you have an ADOStore, misfires are persisted. Thus "if the power goes out", when restarting...you can recover from misfires.
If you have a RamStore...if "the power goes out", everything was in memory to begin with..so you won't get mis-fire handling, because everything was "in memory" and the memory is lost.
..
If you use Sql Server (AdoStore) and put a Profiler/Trace on it, you'll see the engine "poll" for misfires.......with a "go back this far in time" based on the misfireThreshold.
See this link:
http://nurkiewicz.blogspot.com/2012/04/quartz-scheduler-misfire-instructions.html
for more detailed info. Which has a "withMisfireHandlingInstructionFireAndProceed" note.