Memory leak on windows

[tubzby]

I'm using the latest version 0.6.1 (asyn api) on Windows, quickly after I finished my code and tested it on Windows 11, I noticed that the memory consumption continued to increase(over 1MB increase in 1 second) and never got freed, so I used Visual Studio to detach to the process and take several memory snapshots to take a close look into this, please check the attached images, from my prospect of view, it's likely coming from wintun crate or even windows crate, can anybody look into this?

[e1732a364fed]

代码上怎么写的呢？直接用的 example 吗

[tubzby]

@e1732a364fed run the example first, it can read/write to the tun interface, anything other than that should be your own job.

[e1732a364fed]

@e1732a364fed run the example first, it can read/write to the tun interface, anything other than that should be your own job.

我是在问，你这个 memory leak 的issue 是由什么代码造成的。你没理解我的意思。比如说，example 的代码是不是就会有你这个 issue 的问题

[e1732a364fed]

@e1732a364fed run the example first, it can read/write to the tun interface, anything other than that should be your own job.

为什么理解中文如此难呢？你的截图中有中文

[tubzby]

@e1732a364fed run the example first, it can read/write to the tun interface, anything other than that should be your own job.

我是在问，你这个 memory leak 的issue 是由什么代码造成的。你没理解我的意思。比如说，example 的代码是不是就会有你这个 issue 的问题

不是example代码，按照自己的需要加的，我看能不能提供一个能重现问题的mini-example

[chen2ding]

内存泄露，有定位到具体原因吗

[chen2ding]

这个地方需要判断cached大小，然后在处理数据（图中直接丢弃），否则程序会崩溃

[tubzby]

一直没有处理，我这里不会崩溃，只是内存泄漏。

[chen2ding]

把这段删掉就好了，感觉是造成了tokio泄露了

[tubzby]

我也感觉这个地方有问题，一直会启动线程。

[tubzby]

Got the time to look into this lately, the problem is that Queue::poll_read will fork a new thread if no data is ready, but there might be another thread already polling, which may result in a bunch of threads all stuck in polling, cause a memory leak.

The fix is simple, check if the polling thread is running before creating.

The most important thing is that Queue::poll_read might fired multiple times even if the previous poll_read is in Poll::Pending state.

loop {
  // in this case, Queue::poll_read will fire once no more than 10ms, even if no data is available.
  tokio::select!{
    _ = sleep_10ms() => {},
    msg = dev.next() => {},
  }
}

[cavivie]

Hi, I suggest you try the new version of thetun, this problem may not occur.