Preload in QMC and Cache in Access Point

[CVR]

Hello Qlik Geeks,

I have few questions

1. How exactly Preload option works because even after enabling it in QMC still we are having slow rendering objects on the access point?

2. Will the application perform better, If the application stays on the access point for long time without any new application publishes from the publisher and overrides it? (I mean cache will cleared completely with everytime reloaded application overrides on the server)

3. What is best way to deal with slow rendering objects (Text objects) on the access point?

4. How exactly export to excel works? because sometimes when I export to excel I get a blank one and second time I get the values?

5. If a developer directly works on the Prod qvw every time and saves it , will the copy get corrupted ? Always it is better to work on the desktop and replace the qvw's in prod?

6.  What makes the server to lock a QVW and doesn't open/delete most of the times?  Every QVW is also stored in  Publisher and Server memory which is not visible anywhere?

Thanks in Advance,

CVR

[Brett_Bleess · Accepted solution]

Veera, have a few things that may help, but this is all really something I would suggest you contact your account manager about to see if they can arrange for a conversation regarding your use cases etc. and architecture to help you get things on the correct track.  The community is not really the right place to try to resolve this given there are a lot of factors involved that need to be part of the discussion here, so I would definitely reach out to your account manager and see if they can arrange a call to have a conversation with you regarding how to get you on the right track with everything.

The preload option loads the QVW into memory when the QVS service scans the .meta files every 10 minutes by default and sees setting for any QVW that is supposed to be preloaded.  You are correct though, if you are reloading the app during the day with new data, that is likely going to negate many of the cached views etc. which would result in things having to recalculate...  Preloading will NOT help a poorly designed app/data model though.

The Export to Excel issue may be related to the need to increase a timeout, here is an article for that:

Large Exports to Excel and settings to change 

Ajax Client socket timeout settings 

It is not recommended to have developers doing development work on the QlikView Server machine, as that is going to impact the performance/user experience due to the resources being consumed by the developers, it is best practice for the developers to work locally or have their own development server.

If a QVW is opened and then opened again by someone else, if the second person then makes changes and saves, the first person will get a warning about things having been updated since they opened the app etc.  I would venture the more likely issue you are potentially having is anti-virus running active scanning, which we do not recommend as well:

https://help.qlik.com/en-US/qlikview/April2019/Subsystems/Server/Content/QV_Server/QlikView-Server/Q...

Scroll down to the Completing the Installation section to see the note about anti-virus and other related utilities performing scans.

Here is an article link which has a PDF attached that explains in pretty decent detail how the QIX engine uses memory and CPU that may be helpful:

QIX Engine memory and CPU Usage explained 

Hopefully this helps to a degree, again, I would recommend reaching out to your account manager to arrange a broader discussion as well.

Regards,
Brett