Ok guys, this is a strange one and I can't see anything obvious that would explain it...
I've got a pipeline with an IF condition, this IF condition only has a single 'copy data' activity in it. My confusion is that when monitoring this pipeline as its been triggered by a scheduled trigger, the IF condition often takes a lot longer than the only activity, the 'copy data' activity, that it contains. See screen shot below, where the 'copy data' has only taken 7:47mins but the IF condition has a duration of 16:16mins!?!?!
Does anyone know what this means, and what might be causing it? Note... the IF condition itself is only a simple check of a variable that has previously been set before...
At first I thought it was because the 'copy data' was queueing, but as there's no input/output information on an IF condition in the monitor I've no idea what's going on. Surely the IF condition isn't taking several minutes to evaluate its expression??
When you read the "Duration" time, that it is end-to-end for the pipeline activity. That takes into account all factors like marshaling of your data flow script from ADF to the Spark cluster, cluster acquisition time, job execution, and I/O write time. So the "Duration" time will be longer than actual execution time.
Therefore, the IF conditional activity is waiting for the response from the copy activity successfully ended and close all diu resources. But there is very little official information about this explanation.:(
By the way, the "Duration" time of the IF condition activity is not chargeable. You can click this link to see run consumption.
IF condition activity is is billed according to runs at first line. The copy activity is billed according to diu. So we don't need to worry about the "Duration" time of the IF condition activity. :)
Related
I have a Dag A, It runs at a time let's say 10 Am, and typically completes within 15-20 mins, but sometimes it takes more time and due to some tables in the Database it goes into an endless running state, how can I know that if my DAG is completed within a given time frame and if not it should send email Alerts that it's not completed in this time and you need to check.
My thought process:
To build a parallel DAg or process within the same DAG and then write a python function in it which just checks the start time and match it with the Current time and then keeps subtracting it unless it reaches some fixed value lets say 10 mins and then shoots an email that it has not been completed.
Please correct me if I am wrong or what are the other ways to check it
It sounds like you just need to define an SLA. You can find an example here.
Context
I have created a streaming job using Azure portal which aggregates data using a day wise TUMBLINGWINDOW. Have attached a code snippet below, modified from the docs, which shows similar logic.
SELECT
DATEADD(day, -1, System.Timestamp()) AS WindowStart
System.Timestamp() AS WindowEnd,
TollId,
COUNT(*)
FROM Input TIMESTAMP BY EntryTime
GROUP BY TumblingWindow(day, 1), TollId
Now that the job has been running and can see it producing output I want to be able to reduce the costs ideally by setting some sort of time scheduling so that the job can run and still produce the same output without being on all the time.
The only real constraint being that the aggregated output at the end of each TUMBLINGWINDOW has to remain the same as if it were running all the time (no impact of stop-starting on output).
This then brings me to my question.
Update: 2021-02-28
Before going into the question another thing that drove me was that through Azure portal you can manually start and stop a job. When you start/restart a job you can set a custom start time for the job/query. With this level of control say I start a job (or have a job running) and then decide to stop it for majority of the day and then turn it on at say 11:30pm each day with a custom start time of midnight of the current day then it would be able to be on for approx 30min before it would output the results (yet still to my understanding produce the same aggregation results/effect compared to if it was on the whole day up until that point). This job could then be paused again at 00:30am ( the next day for which it stays paused for the majority of the day (1380min total until 11:30pm again) upon which the same above logic is applied.
This way it remains off the majority of the day yet still can produce the same output for each day wise window (correct me if I am wrong in my thinking). The only issue with this to me seems to be the fact someone would have to manually perform this. Thus I was driven to the docs looking for a way to automate this.
Question
How can I start and stop a job in an automated fashion such that the required output would still remain intact but so that the job doesn't have to remain on all the time (like it currently is)?
Does the documentation linked above suffice given the context above, if so what are some possible arrangements for the N minutes (on) and M minutes (off) time variables for this to work?
Is this possible given the scenario that I want to aggregate on a one day TUMBLINGWINDOW window (whereby I want each window to start and end at midnight of each day, as per its default behaviour.)?
Eg
Window start: 2022-02-20 00:00:00 Window end: 2022-02-21 00:00:00 (aggregation performed),
Window start: 2022-02-21 00:00:00 Window end: 2022-02-22 00:00:00 (aggregation performed),
Window start: 2022-02-22 00:00:00 Window end: 2022-02-23 00:00:00 (aggregation performed),
....so on
Thoughts
I found this documentation from Microsoft regarding auto-pausing jobs using a few methods
However came across a paragraph (quoted below) which made me doubtful whether it seems reasonable in my particular use case (TUMBLING 1 day window as described in my question section).
Note
There are downsides to auto-pausing a job. The main ones being the loss of the low latency /real time capabilities, and the potential risks from allowing the input event backlog to grow unsupervised while a job is paused. Auto-pausing should not be considered for most production scenarios running at scale.
Could this method
There are 3 ways to lower costs:
downscale your job, you will have higher latency but for a lower cost, up to a point where your job crashes because it runs out of memory over time and/or can't catch up with its backlog. Here you need to keep an eye on your metrics to make sure you can react before it's too late
going further, you can regroup multiple queries into a single job. This job most likely won't be aligned in partitions, so it won't be able to scale linearly (adding SUs is not guaranteed to give you better performance). Same comment as above, plus you need to remember that when you need to scale back up, you probably will have to break down that job into multiple jobs to again be able to scale in a linear fashion
finally you can auto-pause a job, one way to implement that being explained in the doc you linked. I wrote that doc, and what I meant by that comment is that here again you are taking the risk of overloading the job if it can't run long enough to process the backlog of events. This is a risky proposition for most production scenarios
But if you know what you are doing, and are monitoring closely the appropriate metrics (as explained in the doc), this is definitely something you should explore.
Finally, all of these approaches, including the auto-pause one, will deal with tumbling windows transparently for you.
Update: 2022-03-03 following comments here
Update: 2022-03-04 following comments there
There are 3 time dimensions here:
When the job is running or not: the wall clock
When the time window is expected to output results: Tumbling(day,1) -> 00:00AM every day, this is absolute (on the day, on the hour, on the minute...) and independent of the job start time below
What output you want produced from the job, via the job start time
Let's say you have the job running 24/7 for multiple months, and decide to stop it at noon (12:00PM) on the 1st day of March.
It already has generated an output for the last day of February, at 00:00AM Mar1.
You won't see a difference in output until the following day, 00:00AM Mar2, when you expect to see the daily window of Mar1, but it's not output because the job is stopped.
Let's start the job at 01:00AM Mar2 wall clock time. If you want the missing time window, you should either pick a start time at 'when last stopped' (noon the day before), or a custom time any time before 23:59PM Mar1. What you are driving is the output window you want. Here you are telling ASA you want all the windows from that point onward.
ASA will then reload all the data it needs to generate that window (make sure the event hub has enough retention for that, we don't cache data between restarts in the job): Azure Stream Analytics will automatically look back at the data in the input source. For instance, if you start a job “Now” and if your query uses a 5-minutes Tumbling Window, Azure Stream Analytics will seek data from 5 minutes ago in the input. The first possible output event would have a timestamp equal to or greater than the current time, and ASA guarantees that all input events that may logically contribute to the output has been accounted for.
With an Azure Data Factory "Tumbling Window" trigger, is it possible to limit the hours of each day that it triggers during (adding a window you might say)?
For example I have a Tumbling Window trigger that runs a pipeline every 15 minutes. This is currently running 24/7 but I'd like it to only run during business hours (0700-1900) to reduce costs.
Edit:
I played around with this, and found another option which isn't ideal from a monitoring perspective, but it appears to work:
Create a new pipeline with a single "If Condition" step with a dynamic Expression like this:
#and(greater(int(formatDateTime(utcnow(),'HH')),6),less(int(formatDateTime(utcnow(),'HH')),20))
In the true case activity, add an Execute Pipeline step executing your original pipeline (with "Wait on completion" ticked)
In the false case activity, add a wait step which sleeps for X minutes
The longer you sleep for, the longer you can possibly encroach on your window, so adjust that to match.
I need to give it a couple of days before I check the billing on the portal to see if it has reduced costs. At the moment I'm assuming a job which just sleeps for 15 minutes won't incur the costs that one running and processing data would.
there is no easy way but you can create two deployment pipelines for the same job in Azure devops and as soon as your winodw 0700 to 1900 expires you replace that job with a dummy job using azure dev ops pipeline.
An ADF pipeline needs to be executed on a daily basis, lets say at 03:00 h AM.
But prior execution we also need to check if the data sources are available.
Data is provided by an external agent, it periodically loads the corresponding data into each source table and let us know when this process is completed using a flag-table: if data source 1 is ready it set flag to 1.
I don't find a way to implement this logic with ADF.
We would need something that, for instance, at 03.00 h would trigger an 'element' that checks the flags, if the flags are not up don't launch the pipeline. Past, lets say, 10 minutes, check again the flags, and be like this for at most X times OR until the flags are up.
If the flags are up, launch the pipeline execution and stop trying to launch the pipeline any further.
How would you do it?
The logic per se is not complicated in any way, but I wouldn't know where to implement it. Should I develop an Azure Funtions that launches the Pipeline or is there a way to achieve it with an out-of-the-box AZDF activity?
There is a UNTIL iteration activity where you can check if your clause.
Example:
Your azure function (AF) checking the flag and returns 0 or 1.
Build ADF pipeline with UNTIL activity where you check the output of AF (if its 1 do something). In UNTIL activity you can have your process step. For example, you have a variable flag that will before until activity is 0. In your until you check if it's 1. if it is do your processing step, if its not, put WAIT activity on 10 min or so.
So you have the ability in ADF to iterate until something it's not satisfied.
Hope that this will help you :)
I have a Client Request for my Data Factory Solution
They want to run my Data-Factory when ever the i/p file is available in the Blob Storage/any location.To be very clear they doesn't want to run the solution in an schedule basis,because some day the file won't shows up.So i want an intelligence to search whether the file is available to be process in the location or not.If yes then i have to run my Data factory Solution to process that file,else no need to run the Data factor
Thanks in Advance
Jay
I think you've currently got 3 options to dealing with this. None of which are exactly what you want...
Option 1 - use C# to create a custom activity that does some sort of checking on the directory before proceeding with other downstream pipelines.
Option 2 - Add a long delay to the activity so the processing retires for the next X days. Sadly only a maximum of 10 long retires is allowed currently.
Option 3 - Wait for a newer version of Azure Data Factory that might allow the possibility of more event driven activities, rather than using a scheduled time slice approach.
Apologies this isn't exactly the answer you want. But this gives you current options.