Data Source Refresh causing Offline Cache

[dakridge]

I've had a similar question on the forum before with only half an answer.  As an example, I create a simple datasource link to a Sharepoint calendar.  In a single screen app, I create a gallery that displays events from that linked calendar if they are on todays' date.   I want the app (running on an iPad) to refresh every few minutes to see if any new calendar events were added for the day.  I add a timer set it for 2 minutes and call a refresh on the datasourch at the timer's endpoint.   It's simple and it works great.  The problem is the refresh causes a build up of off line cache that eventually fills the space on the iPad and it crashes.  It takes a few days, but it happens.  There is a manual clear cache in Powerapps' menu, but I don't want to manually clear the cache every few days. 

I see where some are putting data into collections and show commands to clear offline cache.  The problem I have read is, you still have to do a refresh on the datasource to update the collection.  That seems to not fix my problem.   I see all over the Internet people show you how to refresh data using a timer.  I can't be the only one having this issue.  Maybe it's so simple to fix and i'm just not seeing it.  

Any suggestions would be appreciated. 

[v-yutliu-msft]

Hi @dakridge ,

There's no very good to clear cache automatically currently.

If you want to use a Timer to refresh data, you could refer this link:

https://powerusers.microsoft.com/t5/General-Discussion/browser-cache-issues/m-p/197635

I could only suggest you clear your cache once in a while.

What's more, you could refer this link to improve your app, which will help to reduce cache:

https://baizini-it.com/blog/index.php/2017/09/13/powerapps-improving-app-performance/

If your cache problem really affect your experenice, I suggest you open a ticket here:

https://powerapps.microsoft.com/en-us/support/pro/ticket/

Best regards,

[dakridge]

Neither of these suggestions apply to the problem I am having.  I used the article you linked on the Timer some time ago to setup the scenario I presented in this thread.  I cannot be the only person using an iPad that keeps an app running with a timer loop to refresh a data source that is filling that iPad up with cached data.  I simply cannot go to the app every few days and clear the offline cache.  That's crazy.

The second link deals with complex call and loads and show how you would cache data offline.  That is exactly what I’m trying not to do.  I’ve been 2 years trying to get an answer for this issue.  I’ve even talked with engineers at Ignite in Orlando and nobody can give me an answer.

Do the following and run on an ios device and see if I’m wrong:

1. Create a data source to a SharePoint Calendar List
2. Create a gallery and link it to the data source
3. Add a timer and set it for 1 sec or 10 sec and call a refresh on the endtimer for that data source
   
   

That’s it.  Let it run for about an hour and check the available storage on the iPad before and after.  It will uses gigs of space in a few days.   

[dakridge]

Neither of these suggestions apply to the problem I am having.  I used the article you linked on the Timer some time ago to setup the scenario I presented in this thread.  I cannot be the only person using an iPad that keeps an app running with a timer loop to refresh a data source that is filling that iPad up with cached data.  I simply cannot go to the app every few days and clear the offline cache.  That's crazy.

The second link deals with complex call and loads and show how you would cache data offline.  That is exactly what I’m trying not to do.  I’ve been 2 years trying to get an answer for this issue.  I’ve even talked with engineers at Ignite in Orlando and nobody can give me an answer.

Do the following on an iPad or other IOS device and see if I’m wrong:

1. Create a data source to a SharePoint Calendar List
2. Create a gallery and link it to the data source
3. Add a timer and set it for 1 sec or 10 sec and call a refresh on the endtimer for that data source
   
   

That’s it.  Let it run for about an hour and check the available storage on the iPad before and after.  It will uses gigs of space in a few days.   

[dakridge]

After submitting a ticket to Microsoft and receiving a call from support desk, it was determined that there was no fix for this situation.  They understand it is happening on the IOS device but say that the Browser based apps has no access to clear the local cache on the iPad.   The app that is installed to run the Powerapps app can clear the cache from a manual process in the menu.  This is just not satisfactory when an app is running 24/7.   The team in India could not duplicate the issue because they said they had no access to iPads.  Go figure. 

I have extended the time of the refresh to lengthen the time I have to manually clear the cache.   I will not be creating more for the campus because I can’t run around and clear the cache every week or so. 

I still can’t believe I’m the only person having this issue, but I guess I am.  I will be at Ignite in Orlando in November ’19 and will be seeking help.