CoreImage memory build up on real device but not on simulator

I'm trying to benchmark a Core Image filter chains memory footprint and notice a weird quirk in instruments.

On a real device, even with a simple Core Image chain, the memory balloons each time I ran the filter. See attached screen shots.

Running on iPhone 17 Pro:

Running on simulator (M2 Macbook Pro)

As you can see there's a huge build up of 4MB "VM: IOSurface" memory on the real device, but the simulator seems to clean it up correctly.

Here's my basic code:

func processImage() {
        guard let inputImage = ContentViewModel.loadImageFromBundle(name: "kitty.HEIC") else {
            print("Failed to load sample_image from bundle")
            return
        }
        
        var outputImage = inputImage
        
        outputImage = outputImage.applyingFilter("CIBloom", parameters: [
            kCIInputRadiusKey: 20,
            kCIInputIntensityKey: 0.8
        ])
        
        DispatchQueue.global(qos: .userInitiated).async {
            
            let data = self.context.jpegRepresentation(of: outputImage, colorSpace: CGColorSpace(name: CGColorSpace.sRGB)!)
            
            if let data = data, let uiImage = UIImage(data: data) {
                DispatchQueue.main.async {
                    self.displayImage = Image(uiImage: uiImage)
                }
            }
            
        }
    }

Why is this happening? Seems like a bug to me or I need to release an object. At the very least makes it challenging to measure memory usage.

Any help is greatly appreciated. Alex