We're using Quartz 1.8.6 in our app. We are using CronTriggers for hourly and nightly jobs. We would like to set things up such that if there is a misfire, we want to skip the job until the next cron time rolls around.
For simple jobs, it appears you can do a
nightlyTrigger.setMisfireInstruction(SimpleTrigger.MISFIRE_INSTRUCTION_RESCHEDULE_NEXT_WITH_REMAINING_COUNT);
However, it appears that this does not work with CronTrigger. What is the Misfire instruction to use in this case?
You want to use CronTrigger.MISFIRE_INSTRUCTION_DO_NOTHING.
SimpleTrigger.MISFIRE_INSTRUCTION_RESCHEDULE_NEXT_WITH_REMAINING_COUNT is telling Quartz that, upon one or more misfires, it must:
reschedule the trigger to fire upon the next scheduled date (not firing, i.e. ignoring, missed executions).
Also, set the "repetitions left" counter as if all missed executions had run correctly (not accounting for missed runs either).
So basically this misfire instruction tells Quartz to do nothing at all, smile and keep going like nothing ever happened. The KEEP CALM of misfire instructions.
The equivalent instruction for Cron triggers is much more aptly named: CronTrigger.MISFIRE_INSTRUCTION_DO_NOTHING.
Related
Alright, so I'm learning codesys in school and I'm using Function-Blocks. However they didn't seem to update when updating local variables, so I made a test, the one you can see below.
As you can see, in the FB below, "GVL.sw1" becomes True, but "a" doesen't. Why does it not become True? I tested a friends code and his worked just fine, but mine doesen't...
https://i.stack.imgur.com/IpPPZ.png
Comment from reddit
You are showing the source code for a program called "main". You have
a task running called "Main_Task". The program and task are not
directly related.
Is "main" being called anywhere.
So i added main to the "main task" and it worked. I have no idea why it didn't work in the real assignment but maybe I'll solve it now that i have gotten this far.
In your example you have 2 programs (PRG): main and PLC_PRG.
Creating a program doesn't mean that it will be executed/run. For that you need to add the program to a Task in the Task Configuration. Each Task will be, by default, executed on every cycle according to the priority they are configured with (you could also have them be executed on an event and etc. instead). When a Task is executed, each program added to that Task will be executed in the order they are placed (you can reorder them any time).
With that said, if you look at your Task Configuration, the MainTask only has the program PLC_PRG added, so only that program will run. The main program that you are inspecting is never even run.
How can I send all resource units from a resource pool to maintenance or break whenever another event in another block occurs?
I'm looking for something like: resourcePool.startMainteinance()
and write it inside a "On start" box in some other block of the flowchart. Of course then I would need to end the maintenance with something like resourcePool.stopMainteinance() and resume all the tasks the resource units were executing.
Any idea? or some idea to pause manually all resources from executing their task and then resume them?
Note: suspending the agent that seized in the size block with the code SizeBlock.suspend() and SizeBlock.resume() is not an option because the resources have preparation tasks and those tasks also need to be paused.
Thank you!
You should use the Downtime block that is designed for this setup.
You can control it any way you like. In your case, myDowntimeblock.startTask(someAgent) and stopTask(sameAgent) work.
Also check the example model named "Maintenance of a Coffee machine": It shows all the other ways of using the block.
Hi I'm new to Quartz Scheduler, i'm implementing it for the first time. I would like to know if the scheduler's start call will even execute the paused jobs? or Paused jobs will only be activated by resume call alone and nothing else. Please help me.
First of all, you can pause a trigger or scheduler, not a job. Do not be confused, that for example IScheduler interface has different pause methods, and one of them for example is PauseJobs(), they all affect triggers:
IScheduler.PauseAll: Pause all triggers - similar to calling PauseTriggers(GroupMatcher) on every group, however, after using this method ResumeAll() must be called to clear the scheduler's state of 'remembering' that all new triggers will be paused as they are added.
IScheduler.PauseTriggers: Pause all of the ITriggers in the groups matching.
IScheduler.PauseJobs: Pause all of the IJobDetails in the matching groups - by pausing all of their ITriggers.
IScheduler.PauseJob: Pause the IJobDetail with the given key - by pausing all of its current ITriggers.
The difference between Pause and StandBy methods may help you to understand what and when will be started:
The Pause methods are used to pause all the existing triggers you have added to scheduler only. This affect existing triggers only, and scheduler is still RUNNING! Any new job/trigger added will still run, and it's not paused! You would have to call Resume to unflag those paused triggers to get them running again.
The Standby is used to place the entire scheduler in "not working" mode, meaning no jobs or triggers will be fire or run, including ones already scheduled, or new ones added. Not until you call Start again.
Here's the situation that I'm trying to describe, and would like to reflect in the org file:
Suppose you started a task, but while working on it you realized that the description of the task must be amended in a way that it justifies that task to be extended. Still you don't want to lose the original estimate, just for historical purposes, so, roughly, what I would like to have would be:
* STARTED Do something seemingly easy
DEADLINE: <2013-06-09>
This should be a breezy
AMENDED: <2013-06-10>
Looks like this will require more effort
The agenda buffer would use the latest date in the task, but it would be still "interesting" to know the original estimate after the task was finished.
There are many options in org-mode for logging or adding notes whenever a task properties change.
Check for example lognotereschedule, which will ask you for a note when rescheduling a task.
You can choose to store all notes and status changes in a special drawer called LOGBOOK in order to avoid clutter.
I have a processing thread that I use to fill a data buffer. Elsewhere a piece of hardware triggers a callback which reads from this data buffer. The processing thread then kicks in and refills the buffer.
When the buffer fills up I am currently telling the thread to wait by:
while( [self FreeWriteSpace] < mProcessBufferSize && InActive) {
[NSThread sleepForTimeInterval:.0001];
}
However when I profile I am getting a lot of CPU time spent in sleep. Is there a better way to wait? Do I even care if the profiles says time is spent in sleep?
Time spent in sleep is effectively free. In Instruments, look at "running samples" rather than "all samples." But this still isn't an ideal solution.
First, your sleep interval is crazy. Do you really need .1µs granularity? The system almost certainly isn't giving you because the processor isn't that fast. I have to believe you could up this to .1 or .01. But that's still busy-waiting which is not ideal if you can help it.
The better solution is to use an NSCondition. In this thread, wait on the condition, and in your processing thread, trigger the condition when there's room to write.
Do be careful with your naming. Do not name methods with leading caps (that indicates that it's a class name). And avoid accessing ivars directly (InActive) like this. "InActive" is also a very confusing name. Does it mean the system is active (In Active) or not active (inactive). Naming in Objective-C is extremely important. The compiler will not protect you the way it does in C# and C++. Good naming is how you keep your programs working, and many parts of ObjC rely on it.
You may also want to investigate Grand Central Dispatch, which is particularly designed for these kinds of problems. Look at dispatch_async() to run things when new data comes in.
However when I profile I am getting a
lot of CPU time spent in sleep. Is
there a better way to wait? Do I even
care if the profiles says time is
spent in sleep?
Yes -- never, never poll. Polling eats CPU, makes your app less responsive, eats battery, and is an all around waste.
Notify instead.
The easiest way is to use one of the variants of "perform selector on main thread" (see NSThread's documentation). Or dispatch to a queue (including something like dispatch_async(dispatch_get_main_queue(), ^{ ... yo, data be ready ...});).