QVD long running

[vijay4b4]

Hi,

A QVD has been long running for 18 hours which usually takes around half an hour to complete its run. It is causing the server to hang. And it automatically completes its run on the next day. It fails on some days and successful runs on some days. This has been hapening since last 6 weeks. 

Can anyone help me find the possible root cause and solution for this?

#qmc QlikView   

[Miguel_Angel_Baeyens]

How big is that QVD? Are there any errors on the logs?

If your QVD is on the same server where QlikView is running, check RAM and CPU usage at the time of the reload. It could happen that since the load on the QlikView side is high, the reload, which also needs the QlikView server, does not find the required resources and it stalls or fails.

If it is on a separate server, check the network at the time of the reload. QlikView will need to copy that file locally and open it. If there's a lot of traffic on that network, or bandwidth is limited, the file will take a long time to be open by QlikView, written with fresh data, and then stored.

[vijay4b4]

Hi, thanks for the response. However, the error showing up in the logs is:

"failed to allocate qlikview engine". 

What does this mean?

[Maria_Halley]

@vijay4b4

You need an engine for each reload. If there are no available engines, QlikView will try to get one for 45 minutes. If there are no available engines after that time. The reload will fail with this message.

You can set the number of simultaneously running jobs, by changing the "Max number of simultaneous engines".

However there are many factors to consider here. If you set to many engines the system will run out of recourses.

Here is a great 3 good articles about this.

https://community.qlik.com/t5/Knowledge/How-to-increase-and-how-many-reload-engines-QVB-to-allow-in-...

https://community.qlik.com/t5/Knowledge/How-to-increase-and-how-many-reload-engines-QVB-to-allow-in-...

https://community.qlik.com/t5/Knowledge/Scaling-the-QlikView-Publisher/ta-p/1717686

[vijay4b4]

Hi Maria,

There are a lot of QVDs running succesfully but only one particullar QVD is failing repeatedly. But without any debugging, it is running succesfully the next day. If its the case of unavailability of engine, other qvds also should fail, right? but only one QVD is failing everytime.

[vijay4b4]

There are about 500 QVDs with a lot of them are of the same size but only one particular QVD is failing everytime. 

[Maria_Halley]

@vijay4b4

If this always one specific task, I would focus on that task. Has something changed in the script, is there more data to load?

You can check how many engines are in use at the time. If there are no more available engines, there are other tasks that have not finished.

You can also check the document log, to see if it hangs in the same place (but if there are no engine it will not start at all)

https://community.qlik.com/t5/Knowledge/How-To-Enable-QlikView-Document-Reload-Log/ta-p/1710459
https://community.qlik.com/t5/Knowledge/QlikView-12-Distribution-Service-is-not-generating-document-...

You don't mention a version, but if it is April 2020 (12.50) then this might be relevant
https://community.qlik.com/t5/Knowledge/Tasks-stuck-after-upgrade-to-QlikView-April-2020-12-50/ta-p/...

[Maria_Halley]

@vijay4b4

Did you find a solution to the issue?