On Sat, 21 Sep 2013 15:50:47 GMT, simendsjo wrote:

..I've actually never had vibe correctly handling many requests in my tests.

I reach about 4000 req/s. 

weighttp -n10000 -c100 -t2 -k http://localhost:8181/

It can run fine a couple of times, and then it breaks.
Weighttp says `error: connect() failed: Cannot assign requested address (99), while vibe says Handling of connection failed: Error writing data to socket. Remote hung up?`.

You're running out of sockets.
http://redmine.lighttpd.net/projects/weighttp/wiki#Troubleshooting