diff --git a/docs/source/settings.rst b/docs/source/settings.rst
index a322b615..9fef88ec 100644
--- a/docs/source/settings.rst
+++ b/docs/source/settings.rst
@@ -836,7 +836,7 @@ The callable needs to accept a single instance variable for the Arbiter.
 .. code-block:: python
 
         def pre_request(worker, req):
-            worker.log.debug("%s %s" % (req.method, req.path))
+            worker.log.debug("%s %s", req.method, req.path)
 
 Called just before a worker processes the request.
 
diff --git a/gunicorn/config.py b/gunicorn/config.py
index a41bd21c..64a12506 100644
--- a/gunicorn/config.py
+++ b/gunicorn/config.py
@@ -1906,7 +1906,7 @@ class PreRequest(Setting):
     type = callable
 
     def pre_request(worker, req):
-        worker.log.debug("%s %s" % (req.method, req.path))
+        worker.log.debug("%s %s", req.method, req.path)
     default = staticmethod(pre_request)
     desc = """\
         Called just before a worker processes the request.
diff --git a/gunicorn/workers/ggevent.py b/gunicorn/workers/ggevent.py
index 0a844db3..5c41f14e 100644
--- a/gunicorn/workers/ggevent.py
+++ b/gunicorn/workers/ggevent.py
@@ -110,7 +110,7 @@ class GeventWorker(AsyncWorker):
                 gevent.sleep(1.0)
 
             # Force kill all active the handlers
-            self.log.warning("Worker graceful timeout (pid:%s)" % self.pid)
+            self.log.warning("Worker graceful timeout (pid:%s)", self.pid)
             for server in servers:
                 server.stop(timeout=1)
         except Exception: