System is flooded with failed read(2) calls: Resource temporarily unavailable (errno=35) coming from xorg unix socket

[Yuri]

> Ok, so something is really really odd here. Are you able to dig deeper
> into what the socket code in xorg is doing wrong? It'd certainly be
> nice to fix all of this stuff up.
>
> Thanks so much for digging into this! It's been annoying me, but I've
> just been ridiculously busy trying to bring up some more Atheors wifi
> chipset support in FreeBSD.

Now it is clear what is happening.
Xlib routinely calls read one more time during every X-protocol call one 
extra time, kinda just in case. And such calls always fail with EAGAIN, 
unless disconnect or socket error happens to happen at this time. This 
essentially about doubles the number of system calls that any X app makes.

Yuri