by cw@f00f.org:

What steps will reproduce the problem?
1. build the code, sometimes the websocket test hangs
2. if it doesn't, cd src/pkg/websocket/

  make test
  <watch>

usually only a few attempts is needed for me; f.e.:

  cw@lysdexia:~/wk/go/go.hg/src/pkg/websocket$ for t in {1..100} ; do ./6.out ; done
  [...]
hangs within a few iterations

this never hangs:
  cw@lysdexia:~/wk/go/go.hg/src/pkg/websocket$ for t in {1..100} ; do GOMAXPROCS=2 ./6.out ; done
  [...]


What is your $GOOS?  $GOARCH?

linux amd64



Which revision are you using?  (hg identify)

6ccdfb494664+ tip



FWIW, the hang is inside "ws.Close();" at the end of websocket_test.go though
it's not clear why 
to be looking at this.  The hang is not in the main thread of execution as you can see:

  write(7, "\0hello, world\n\377"..., 15) = 15
  read(7, "\0hello, world\n\377"..., 4096) = 15
  fcntl(7, F_GETFL)                       = 0x802 (flags O_RDWR|O_NONBLOCK)
  fcntl(7, F_SETFL, O_RDWR)               = 0
  write(5, "\0"..., 1)                    = 1
  close(7)                                = 0
  futex(0x4aae48, FUTEX_WAIT, 3, {1073741824, 0}

and another (OS) thread is burning all the CPU.  That thread is not making any system
calls (I 
thought perhaps the socket close was causing some goroutine to spin on an error, but
that would 
show up tracing the thread that's consuming all the CPU cycles).