buffer object leaking memory

[janmarcheckman]

I have a program that is leaking memory.
It seems to be related to the fact that I'm creating a buffer every frame.
As far as I understand wgpu objects should free their resources on drop.
Am I correct that this shouldn't leak memory? Or am I missing something?

I've written the simplest program I could that still exhibits the behavior:

fn main() {
    use wgpu::util::DeviceExt;

    let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
        backends: wgpu::Backends::all(),
        ..Default::default()
    });
    
    let adapter = pollster::block_on(instance.request_adapter(&wgpu::RequestAdapterOptions {
        power_preference: wgpu::PowerPreference::HighPerformance,
        force_fallback_adapter: false,
        compatible_surface: None,
    })).unwrap();

    let (device, _queue) = pollster::block_on(adapter.request_device(&wgpu::DeviceDescriptor {
        label: None,
        required_features: wgpu::Features::empty(),
        required_limits: wgpu::Limits::default()
    }, None)).unwrap();

    let contents = &[0, 0, 0, 0];

    let buffer_init_descriptor = &wgpu::util::BufferInitDescriptor {
        label: None,
        contents,
        usage: wgpu::BufferUsages::UNIFORM,
    };

    loop {
        let _buffer = device.create_buffer_init(buffer_init_descriptor);
    }
}

[package]
name = "test_buffer_leak"
version = "0.1.0"
edition = "2021"

[dependencies]
wgpu = "0.20.1"
pollster = "0.3.0"

I'm on windows 10
The backend that gets selected is Vulkan

[teoxoy]

The destruction is currently deferred to Queue.submit()/Surface.configure()/Device.poll(), with #5910 it will happen either immediately if there are no submissions using that resource or otherwise deferred at the end of the submission.

[teoxoy]

Ok, you previously mentioned win 10, vulkan, is it a release or debug build?

How big is the leak you are seeing (ex ~X MB/min)? Also, is it a CPU or GPU memory leak (I was assuming CPU)?

If I still can't repro it, the GPU model and driver version would help.

[janmarcheckman]

Windows 10 and Vulkan is correct
I've been testing with debug build.
Seems to be leaking 0.5 MB/s.
I'm looking at CPU memory.
GPU: NVIDIA GeForce GTX 1070
Driver Version: 31.0.15.4601

[cwfitzgerald]

Try with a release build, or with InstanceFlags::empty()

[janmarcheckman]

I've graphed the cpu memory usage every minute for 10 minutes for the different combinations of release/debug and InstanceFlags::empty()/default.

[teoxoy]

This sounds like #5478. Thanks for investigating!

[teoxoy]

I filed #6053.