strange timeout error returned by kevent() in 6.0

[Igor Sysoev]

I found strange timeout errors returned by kevent() in 6.0 using
my http server named nginx.  The nginx's run on three machines:
two 4.10-RELEASE and one 6.0-BETA3.  All machines serve the same
content (simple cluster) and each handles about 200 requests/second.

On 6.0 sometimes (2 or 3 times per hour) in the daytime kevent()
returns EV_EOF in flags and ETIMEDOUT in fflags, nevertheless:

1) nginx does not set any kernel timeout for sockets;
2) the total request time for such failed requests is small, 30 and so seconds.


Igor Sysoev
http://sysoev.ru/en/