On Fri, Aug 12, 2011 at 11:36 PM, Mark Ellzey <mtho...@strcpy.net> wrote:
> On Fri, Aug 12, 2011 at 09:48:20PM +0300, about bus wrote:
> > I've added some debug output in libevent functions, added "fd" (file
> > descriptor) in every output message.
> > messages from libevent - [warn]
> > messages from my http server - v[3]
> > Also I've changed timeout in nginx config from 75 to 30, it does not
> > increase or decrease timeouts count.
> > I've got about 0.1% timeout errors independently from timeout value.
> >
> > Log output for one of timeouted requests:
> >
> > 2011.08.12 21:30:02 [warn] === evhttp_get_request_connection: fd: 142
> new
> > request from 127.0.0.1:49242
> > 2011.08.12 21:30:32 [warn] === event_active: 0x802a84480 (fd: 142),
> res
> > 2, callback 0x8007970f0
>
> Hrmm - looks like DNS
>
> evhttp_get_request_connection(
> struct evhttp* http,
> evutil_socket_t fd, struct sockaddr *sa, ev_socklen_t salen)
> {
> struct evhttp_connection *evcon;
> char *hostname = NULL, *portname = NULL;
>
> name_from_addr(sa, salen, &hostname, &portname);
>
>
> eventually calling gethostbyaddr().
>
>
> My guess is that it can't resolve the address.
>
> If this is the case, that's actually not the right thing to do (on
> levent side).
>
>
I've checked this, domain name resolution does not take much time.
Issue somewhere between end of evhttp_socket_cb and start of evhttp_read_cb
functions calls.
2011.08.14 16:52:27 [warn] === evhttp_socket_cb: fd: 131
2011.08.14 16:52:27 [warn] === evhttp_get_request_connection: fd: 131 new
request from 127.0.0.1:53282
2011.08.14 16:52:27 [warn] === evhttp_get_request_connection [[before
return]]: fd: 131 ### return from function
2011.08.14 16:52:27 [warn] === evhttp_start_read: fd: 131
2011.08.14 16:52:27 [warn] === evhttp_socket_cb [[before return]]: fd: 131
### return from function
2011.08.14 16:52:57 [warn] --- event_active: 0x803032390 (fd: 131), res 2,
callback 0x800797140
2011.08.14 16:52:57 [warn] === evhttp_read_cb: fd: 131 len: 401: data: GET
/qyery/xxx/yyy/ <-- headers --->
