Memory leak when recreate canvas

[antonkarytski]

Hey, found one curious case on iOS (im not sure, but probably this problem on Android as well, still investigate)
We have screen with GCanvas, after some attempts to open this screen, we got crashes.
Test shows, after closing screen, memory doesn't clean, and i think GCanvas still remain in memory after close. So ios terminate process due overusing memory

Screen.Recording.2022-05-12.at.13.30.06.mov

[flyskywhy]

The yellow page of "Just Canvas", is it:

a yellow image by ctx.drawImage()

or

ctx.fillStyle = 'yellow' then ctx.fillRect()

?

[antonkarytski]

@flyskywhy thats just a background of View

return (
                <View
                  style={{
                    flex: 1,
                    backgroundColor: "yellow",
                  }}
                >
                  <GCanvasView
                    onCanvasCreate={(r) => {
                      ref.current = r.getContext("2d");
                    }}
                    style={{
                      width: Dimensions.get("screen").width,
                      height: Dimensions.get("screen").height,
                    }}
                  />
                </View>
              );

[yoral-wang]

I am meeting the same problem

[flyskywhy]

fixed by @flyskywhy/react-native-gcanvas@2.3.22

[frenkie]

Still having the same problem in fixed version 2.3.22. Just 1 component with a button to switch to a render state with or without GCanvasView.
After 7 switches the app kills itself with a Memory warning (pressure level: TRIM_MEMORY_RUNNING_CRITICAL) received by JS VM, running a GC error.

My onCanvasCreate method:

  const initCanvas = can => {
    can.getContext('2d').fillStyle = 'white';
    can.getContext('2d').fillRect(0, 0, can.width, can.height);
  };

Not using any local variables to make sure memory doesn't leak there.

[flyskywhy]

2.3.22 just fixed the issue in iOS, because I test and found it's already OK on Android.
Please paste the code of your "switch to a render state with or without GCanvasView"

[Loovery]

The memory leak is still here. :(
This happens when I unmount component with GCanvasView

[avanlaningham]

Hi flyskywhy, I am working with Loovery (Grigory) here and we are not experts in objective c/ios code and these memory leaks. If there is anyway I could inspire you to help us find the problem please let me know. We love what you have done here. We are a startup but still we have a commercial product that is making us some money, so I would pay you to help us.

[flyskywhy]

@Loovery @avanlaningham , OK, I can try 😄

1. Does the memory leak happen on Android or iOS?
2. How many Bytes leak every time unmount component(It's better to also offer a screen video record here)?
3. How many times unmount component will leak big enough to let the app kills itself?

[Loovery]

@flyskywhy

1. Only iOS.
2. ~15mb on empty project.
3. It all depends on the device and the amount of free memory.

code

memory-leak.mov

[avanlaningham]

But Grigory normally it was about 6 times or something that it would crash after. Giving rough number might help him better understand.