I have noticed a dramatic decrease in performance after adding some very large image. I have made it large by mistake, it's actually about 6000x6000 webp image, placed in

drawable-xxxhdpi

, and I render it like so:

Box(modifier = Modifier.fillMaxWidth()) {
  Image(
    modifier = Modifier.matchParentSize().padding(19.dp),
    painter = painterResource(id = R.drawable.impossibly_large_image),
  )
  Image(
    painter = painterResource(R.drawable.regular_sized_image)
  )
}

Both images have transparency. I have some pointer input which changes parent composable's state, but this Box is isolated in a separate composable function, not depending on any state. And I have GPU profiler on-screen spikes a quite above 16ms line (see thread for a screenshot). If i remove that "oversized image" it immediately falls below 16ms. My question is: shouldn't Compose pre-scale and somehow cache the Image? Are there some steps to encourage such caching?

The performance impact is most likely due to sampling on the GPU hitting uncached data constantly

Have you tried loading it up using a library like Coil?

The performance impact is most likely due to sampling on the GPU hitting uncached data constantly

By sampling do you mean me running this on-screen profiling? Laggy performance is there even with GPU profiling lines disabled. Or do you mean sampling GPU texture (I'm not that experienced in gpu internals...)

I meant sampling as in reading pixel data from the bitmap to draw it on screen.