topic Re: Destruction of objects/graphics does not release memory in Qt Maps SDK Questions

Destruction of objects/graphics does not release memory

NorbertThoden — Wed, 02 Dec 2020 11:38:05 GMT

In your application objects/Graphics are created and destroyed.
Now we recognize that the memory allocated by Esri::ArcGISRuntime::Graphic is not released.
So our application runs out of memory is a few hours (instead of running days and weeks)

I wrote a sample to reproduce the issue:
1) start the program
-> 185MB

2a) I create 100k objects (SimpleMarkerSymbol) -> exisiting objects: 100k:
-> 1008MB

2b) I destroy 100k objects (SimpleMarkerSymbol) -> exisiting objects: 0:
-> 1070MB

3a) create 100k objects..
3b) destroy..
-> exisiting objects: 0:
ctc 3981 15.7 7.2 3351616 1186460 pts/8 Sl+ 08:07 0:11 ./MemUsageWithManyMarker
-> 1180MB

4a) create 100k objects..
4b) destroy..
-> exisiting objects: 0:
ctc 3981 16.3 7.5 3404684 1233580 pts/8 Sl+ 08:07 0:23 ./MemUsageWithManyMarker
-> 1223MB
...

The memory isn´t released even if i destroy the a) the GraphicsOverlay, b) MapView or c) Map.

Following Cases/Bugs are created:

Esri Case #02675513 - Destruction of objects/graphics does not release memory
BUG-000135578: Appending 100,000 graphics to GraphicsOverlay causes memory leak
Esri Case #02688296 - increasing memory usage over time
BUG-000135793 - Creation of an additional 1,000 graphics after initially creating 100,000 graphics causes an increase in memory usage when using dynamic rendering mode

Re: Destruction of objects/graphics does not release memory

LukeSmallwood — Mon, 09 Nov 2020 15:10:39 GMT

Hi Norbert, I hope you're well.

We'll take a look at your repro to try and understand what is going on. In the meantime, one thing which may be of use is to try and avoid creating a new SimpleMarkerSymbol for each Graphic that you allocate:

        Esri::ArcGISRuntime::SimpleMarkerSymbol *sms =

          new Esri::ArcGISRuntime::SimpleMarkerSymbol(Esri::ArcGISRuntime::SimpleMarkerSymbolStyle::Circle, QColor("red"), 10, graphic);

        graphic->setSymbol(sms);

If you can create a SimpleRenderer for the GraphicsOverlay instead, then each Graphic in that overlay will get the same symbol without having to allocate additional memory. This should be a more efficient workflow in general - this sample should give you an idea of how to use that API arcgis-runtime-samples-qt/ArcGISRuntimeSDKQt_CppSamples/DisplayInformation/Simple_Renderer at master · Esri/arcgis-runti… .

I can see that this is a simplified repro project so if you are already doing that in the real example please ignore.

Luke

Re: Destruction of objects/graphics does not release memory

LukeSmallwood — Mon, 09 Nov 2020 15:32:42 GMT

One other thing which may be worth trying is to make sure that individual graphics are removed when you loop round and call

glm->removeOne(graphic);

The call to remove a Graphic is asynchronous and you should wait for the graphicRemoved signal before removing the next. I'm not sure if that is affecting the work-flow that you use here but it may be worth investigation.

Re: Destruction of objects/graphics does not release memory

NorbertThoden — Fri, 20 Nov 2020 12:31:34 GMT

Hi Luke!

Is there an example how to create and destroy graphics as yopu suggested?

Thx