Tablets suddenly slowing down

Survey Solutions user Otim Innocent from Uganda has sent us the following question:

I would like to ask, what could cause the interviewer application to drastically slow down? The application has worked very well in the past year, but this time round … the application slowed down drastically to a very worrying state. I checked to see that there is no heavy validation check to consume memory and maintain consistency.
Please advise on what could be the potential causes of the slowing down on the interviewer application.

The question does not give any clues as to what has changed or could be causing the tablets to slow down. So it is only possible to recommend a very generic sequence of steps to diagnose the issue. I’ve posted these tablet performance diagnostics steps to the support site.

When I tested the questionnaire (using the tester), I also noted that the questionnaire was very slow. It becomes particularly slow when I reach the multiselect categorical questions with the yes/no display button. Have you tried to remove the validation rule that flags an error until all the responses are marked with a yes or a no? If so, any change?

Did you manage to find what question, condition or value caused the problem ultimately?

We have been experiencing slowing down of tablets. After completing 4 to 6 interviews the tablets gets really slow and the memory usage of the Interviewer app can reach to 1.2 GB. To resolve the problem we cleared the app chache and the tablet performance was restore.

Maybe you can consider to clear the app cache programmatically after completing the interview or some other convenient event.

Here an example of how to implement it

Which version are you using?
There were important changes related to this issue recently:

How can the issue be replicated?

We just finished a pilot collecting 15,340 interviews with 90 interviewers
We used version Interviewer App version 22.06.01 (32717)

Thank you @aguinada , this version is newer than the v22.02 I’ve mentioned where the memory leaks were fixed. If you are still observing the slowing down of the tablets, we need the exact steps to be able to reproduce the problem in the lab conditions. Best, Sergiy

Dear @sergiy
Here is a set of videos that show the experience with the tablets we are facing. The Interviewer App version is 22.06.7.

Ecuador Tablet Problems - Google Slides

I hope these videos can provide you with more information.

Thanks, Vladimir.

Video 1 shows a crash while using the map dashboard.
Inspect the crash logs from the tablet to acquire the exact error message.

Dear @aguinada,
Thank you for provided videos.
The first video shows the crash on the Map Dashboard. We will address it.
The remaining videos show performance issues when they already occurred.
Do you have any thoughts about actions that should be performed to get in that state?

As a workaround you may notify your interviewers (while we are investigating this issue) that if the application slows down they could unload the application and start it again. It will start from scratch and performance will be restored.