Nprinting Tasks/Reports in stuck state (forever 'Running' state) - QVDistributionServiceTask gets stuck in Task Manager

[ShubhamKinger]

We have couple of Nprinting reports which run on regular basis as per business. These are run via QMC with the help of Rest API's that Nprinting has exposed. Nprinting holds the data in its cache before sending the report via emails.

But while reloading the data into its cache, it forever remains  in the 'Running' status only  and doesn't proceed further. We have observed, when the memory size of QV distribution service exceeds 2 GB, then the Nprinting becomes unresponsive and no longer creates any QV.exe task in Task Manager details tab.

As a resolution, we try to end the task of 'QvDistributionService.exe' from the task manager but even that takes ample of time on its own and post that we try restarting the Qv Distribution service. Often, it works but if nothing works, then we have to restart all the services/restart the server.

We have the Qlikview and Nprinting installed on the same server. Can this be a potential reason for the issue ?

We have tried many things including changing some of the configuration parameters but it didn't help much. We have tried incorporating Infra team on the same to check heap size and virtual memory allocation but it seems fine there as per the standards.

Is anybody aware about the issue ? or if anyone can throw some light on it ? We are assuming this to be a memory issue but this is still a high level assumption. What can be the possible cause for the same and what can we try to resolve this issue ?

[Lech_Miszkiewicz]

Hi, 

sorry to say but looks like your setup is just wrong.

1 - NPrinitng should run on dedicated machine - your configuration is unsupported and is firts well known and massive "NO"

2 - Fact that your metadata generation process takes long is usually result of wrong development, meaning:

• app which is used is having unsupported objects ( just lookup those on help.qlik.com)
• app is not optimized for NPrinting - given the size of the app you mentioning we normally would build dedicated app so all objects can be optimized and minimized for performance improvement when running reports and generating cache

3. Connection used - in properly setup environment you would use QVP connection (Server/Claster) so you would utilize the fact that app is already loaded on the server memory - I am not sure what connection type you are using. 

REading your description it raises straight away few red flags in my mind so I would start from the absolute minimum and ensure I have dedicated server and that app is fully supported - meaning going through help document: https://help.qlik.com/en-US/nprinting/May2022/Content/NPrinting/GettingStarted/HowCreateConnections/...

cheers

[ShubhamKinger]

Hi Lech,

Thanks for the above points and the explanation.

Currently, we are in the process of migrating our Nprinting set up to a different server. But I would like to know why the reports gets stuck once the memory size of QVdistributionService crosses 2 GB, especially having a RAM of 512 GB at the server level. What is that parameter that decides this limit. 

Isn't the main purpose of Distribution service is to distribute huge amount of data ? and if it's memory size is just limited to 2 GB, isn't that an issue ?

[Ruggero_Piccoli]

Hi @ShubhamKinger ,

You forgot to label the post with the version of Qlik NPrinting you are using. In this case the answer could depend on it because we solved some similar issue and optimized the connections to QlikView. So the first suggestion is to upgrade to latest available version if you did not do that. 

Every computer with a Qlik NPrinting Engine need to have installed also QlikView Desktop with an active license to manage connections to QVWs. Installing Qlik NPrinting and QlikView Server on the same computer is not supported https://help.qlik.com/en-US/nprinting/May2022/Content/NPrinting/DeployingQVNprinting/Supported-unsup... . The process QVDistributionService.exe is not a Qlik NPrinting process, it is a QlikView Server one. So, if you have the QVDistributionService running on the same computer where you installed Qlik NPrinting (Server or Engine), you are in a not supported configuration and the first step is to move your installation to a supported scenario.

Best Regards,

Ruggero

[Lech_Miszkiewicz]

Hi, I think you are missing a point here. QVdistributionService is not used with NPrinting really so the fact that you are experiencing this issue just coincides with the NPrinting running on the same box. 

There is no point discussing more about it until you have supported environment and supported qvw. Once you have that and you still experience issues then we can isolate problems and look at them. At the moment there is no point as this by definition may not work and in your case isn't.

So to answer your question: "Isn't the main purpose of Distribution service is to distribute huge amount of data ?"  - the answer is: yes it is on standalone machine not used for any other purpose (NPrinting server or engine). Then 2GB limit you are experiencing is also strange and I am not aware of such limit in normal supported configuration with normal supported OS (64 bit).  SO if you still have this problem in supported environment then we can have a look at it.

What is your environment, os version, versions of software used etc etc..?