Intermittent hangs

[v1gnesh]

Firstly, thank you for sharing your work ❤️

Inside a tokio async main, I'm using it like this:

use futures_buffered::BufferedStreamExt;


let mut stream = framed_read_stream
    .map(|x| do_stuff(x))
    .buffered_ordered(4096);

while let Some(recvd) = stream.next().await {
}

It just seems to hang, like 80% of the time (i.e., 80% of the time I run the program). How do I debug this?

[conradludgate]

Curious. Do you happen to know what operation "do_stuff" gets stuck on specifically?

[conradludgate]

Although it shouldn't matter here, there is a bug with BufferedOrdered I've just found where the size_hint is incorrec:

futures-buffered/src/buffered/ordered.rs

Line 77 in 2384ae2

_ => (0, Some(0)),

[v1gnesh]

do_stuff creates a tx rx pair, spawns tasks into a pre-created rayon global thread pool giving it the tx, then returns the rx.
So stream is a Stream of Receivers.

[conradludgate]

I think I found a subtle race condition in the waker implementation. Just published a potential fix

[v1gnesh]

Still stalls :(
Works with buffered(1) but you might expect that to work already.

[conradludgate]

Hmm. Unfortunate. I guess I'll keep digging. I've not been able to reproduce any stalls myself yet