My HTTP reverse proxy in front of a bunch of my domains got wedged (didn't fully crash,
but stopped serving).  The last thing in its logs is:

2012/05/02 06:06:49 Error dialing websocket backend 127.0.0.1:8082: dial tcp
127.0.0.1:8082: connection refused
2012/05/02 06:06:49 Error dialing websocket backend 127.0.0.1:8082: dial tcp
127.0.0.1:8082: connection refused
2012/05/02 19:38:22 cgi: copy error: http: response status code does not allow body
2012/05/03 08:01:58 cgi: copy error: http: response status code does not allow body
2012/05/04 03:41:50 CGI error: fork/exec
/home/bradfitz/var/bradfitz.com/cgi-bin/bmlp.pl: too many open files
2012/05/04 03:41:56 http: panic serving 220.181.51.219:59729: pollServer AddFD
epoll_ctl: no such file or directory
/home/bradfitz/go/src/pkg/net/http/server.go:576 (0x436828)
_func_003: buf.Write(debug.Stack())
/home/bradfitz/go/src/pkg/runtime/proc.c:1443 (0x4148f6)
panic: reflect·call(d->fn, d->args, d->siz);
/home/bradfitz/go/src/pkg/net/fd.go:121 (0x462bd8)
(*pollServer).AddFD: panic("pollServer AddFD " + err.Error())
/home/bradfitz/go/src/pkg/net/fd.go:266 (0x463526)
(*pollServer).WaitRead: err := s.AddFD(fd, 'r')
/home/bradfitz/go/src/pkg/net/fd.go:428 (0x4642bb)
(*netFD).Read: if err = pollserver.WaitRead(fd); err == nil {
/home/bradfitz/go/src/pkg/net/tcpsock_posix.go:87 (0x472415)
(*TCPConn).Read: return c.fd.Read(b)
/home/bradfitz/go/src/pkg/io/io.go:394 (0x459cd9)
(*LimitedReader).Read: n, err = l.R.Read(p)
/home/bradfitz/go/src/pkg/bufio/bufio.go:77 (0x49d57d)
(*Reader).fill: n, e := b.rd.Read(b.buf[b.w:])
/home/bradfitz/go/src/pkg/bufio/bufio.go:257 (0x49dfbf)
(*Reader).ReadSlice: b.fill()
/home/bradfitz/go/src/pkg/bufio/bufio.go:283 (0x49e124)
(*Reader).ReadLine: line, err = b.ReadSlice('\n')
/home/bradfitz/go/src/pkg/net/textproto/reader.go:55 (0x4a7169)
(*Reader).readLineSlice: l, more, err := r.R.ReadLine()
/home/bradfitz/go/src/pkg/net/textproto/reader.go:36 (0x4a6f91)
(*Reader).ReadLine: line, err := r.readLineSlice()
/home/bradfitz/go/src/pkg/net/http/request.go:457 (0x42509b)
ReadRequest: if s, err = tp.ReadLine(); err != nil {
/home/bradfitz/go/src/pkg/net/http/server.go:240 (0x428200)
(*conn).readRequest: if req, err = ReadRequest(c.buf.Reader); err != nil {
/home/bradfitz/go/src/pkg/net/http/server.go:594 (0x42a293)
(*conn).serve: w, err := c.readRequest()
/home/bradfitz/go/src/pkg/runtime/proc.c:271 (0x4129fc)
goexit: runtime·goexit(void)