add max_accept parameter to StreamServer

documentation is taken from http://haproxy.1wt.eu/download/1.5/doc/configuration.txt

gevent/server.py

@@ -33,6 +33,10 @@ class StreamServer(BaseServer):
     The delay starts with :attr:`min_delay` and doubles with each successive error until it reaches :attr:`max_delay`.
     A successful :func:`accept` resets the delay to :attr:`min_delay` again.
     """
+    # Sets the maximum number of consecutive accepts that a process may perform on
+    # a single wake up. High values give higher priority to high connection rates,
+    # while lower values give higher priority to already established connections.
+    max_accept = 100
 
     # the number of seconds to sleep in case there was an error in accept() call
     # for consecutive errors the delay will double until it reaches max_delay
@@ -102,37 +106,38 @@ class StreamServer(BaseServer):
             self._start_accepting_timer = None
 
     def _do_accept(self):
-        address = None
-        try:
-            if self.full():
-                self.stop_accepting()
-                return
+        for _ in xrange(self.max_accept):
+            address = None
             try:
-                client_socket, address = self.socket.accept()
-            except socket.error, err:
-                if err[0] == errno.EAGAIN:
+                if self.full():
+                    self.stop_accepting()
+                    return
+                try:
+                    client_socket, address = self.socket.accept()
+                except socket.error, err:
+                    if err[0] == errno.EAGAIN:
+                        return
+                    raise
+                self.delay = self.min_delay
+                client_socket = socket.socket(_sock=client_socket)
+                spawn = self._spawn
+                if spawn is None:
+                    self._handle(client_socket, address)
+                else:
+                    spawn(self._handle, client_socket, address)
+            except:
+                self.loop.handle_error((address, self), *sys.exc_info())
+                ex = sys.exc_info()[1]
+                if self.is_fatal_error(ex):
+                    self.kill()
+                    sys.stderr.write('ERROR: %s failed with %s\n' % (self, str(ex) or repr(ex)))
                     return
-                raise
-            self.delay = self.min_delay
-            client_socket = socket.socket(_sock=client_socket)
-            spawn = self._spawn
-            if spawn is None:
-                self._handle(client_socket, address)
-            else:
-                spawn(self._handle, client_socket, address)
-            return
-        except:
-            self.loop.handle_error((address, self), *sys.exc_info())
-            ex = sys.exc_info()[1]
-            if self.is_fatal_error(ex):
-                self.kill()
-                sys.stderr.write('ERROR: %s failed with %s\n' % (self, str(ex) or repr(ex)))
-                return
-        if self.delay >= 0:
-            self.stop_accepting()
-            self._start_accepting_timer = self.loop.timer(self.delay)
-            self._start_accepting_timer.start(self._start_accepting_if_started)
-            self.delay = min(self.max_delay, self.delay * 2)
+                if self.delay >= 0:
+                    self.stop_accepting()
+                    self._start_accepting_timer = self.loop.timer(self.delay)
+                    self._start_accepting_timer.start(self._start_accepting_if_started)
+                    self.delay = min(self.max_delay, self.delay * 2)
+                break
 
     def is_fatal_error(self, ex):
         return isinstance(ex, socket.error) and ex[0] in (errno.EBADF, errno.EINVAL, errno.ENOTSOCK)