add possibility to add the request PID to the access logs.

gunicorn/config.py

@@ -678,7 +678,7 @@ class AccessLogFormat(Setting):
     cli = ["--access-logformat"]
     meta = "STRING"
     validator = validate_string
-    default = '%(h)s %(l)s %(u)s %(t)s "%(r)s" %(s)s %(b)s "%(f)s" "%(a)s"'
+    default = "%(h)s %(l)s %(u)s %(t)s "%(r)s" %(s)s %(b)s "%(f)s" "%(a)s"'
     desc = """\
         The Access log format .
 
@@ -697,7 +697,8 @@ class AccessLogFormat(Setting):
         f: referer
         a: user agent
         T: request time in seconds
-        D: request time in microseconds
+        D: request time in microseconds,
+        p: process ID
 
         You can also pass any WSGI request header as a parameter.
         (ex '%(HTTP_HOST)s').

gunicorn/glogging.py

@@ -150,7 +150,8 @@ class Logger(object):
                 'f': environ.get('HTTP_REFERER', '-'),
                 'a': environ.get('HTTP_USER_AGENT', '-'),
                 'T': str(request_time.seconds),
-                'D': str(request_time.microseconds)
+                'D': str(request_time.microseconds),
+                'p': "<%s>" % os.getpid()
                 }
 
         # add WSGI request headers