[PATCH wayland] increase server listen queue to 8

[Pekka Paalanen]

On Wed, 15 Oct 2014 16:43:34 +0300
Imran Zaman <imran.zaman at gmail.com> wrote:

> Hi
> 
> This will allow more than 1 simultaneous client connections to the server
> without the possibility of connection refused error. possible use case
> is multiple session
> compositors can connect to the system compositor simultaneously.
> 
> ----
> 
> diff --git a/src/wayland-server.c b/src/wayland-server.c
> index 674aeca..e3b7d9f 100644
> --- a/src/wayland-server.c
> +++ b/src/wayland-server.c
> @@ -1126,7 +1126,7 @@ _wl_display_add_socket(struct wl_display
> *display, struct wl_socket *s)
>   return -1;
>   }
> 
> - if (listen(s->fd, 1) < 0) {
> + if (listen(s->fd, 8) < 0) {
>   wl_log("listen() failed with error: %m\n");
>   return -1;
>   }

This patch is obviously format-broken, but the change itself seems
harmless to me. Since no-one has commented on it, I suppose no-one is
against it.

I also found:
http://utcc.utoronto.ca/~cks/space/blog/unix/ListenBacklogMeaning
which suggests that the number is fairly arbitrary.

I couldn't find a clear explanation what the backlog argument means for
unix domain sockets, either. However, I did find a random comment:
http://stackoverflow.com/questions/19221105/connect-with-unix-domain-socket-and-full-backlog
That suggests that on Linux you might rather see EAGAIN than
ECONNREFUSED. Sounds like it's not completely true?

So, since we have no reason to artificially limit the queue, let's go
with something big. Say, 128.

Would you like to spin a proper patch, or shall I just rewrite this in
my own name?

Would be nice to hear how you actually hit the connection refused, and
on what OS/kernel.


Thanks,
pq