add an option to change access_log using gunicorn

docs/sanic/deploying.md

@@ -15,6 +15,7 @@ keyword arguments:
 - `protocol` *(default `HttpProtocol`)*: Subclass
   of
   [asyncio.protocol](https://docs.python.org/3/library/asyncio-protocol.html#protocol-classes).
+- `access_log` *(default `True`)*: Enables log on handling requests (significantly slows server).
 
 ## Workers
 
@@ -63,6 +64,20 @@ of the memory leak.
 
 See the [Gunicorn Docs](http://docs.gunicorn.org/en/latest/settings.html#max-requests) for more information.
 
+## Disable debug logging
+
+To improve the performance add `debug=False` and `access_log=False` in the `run` arguments.
+
+```python
+app.run(host='0.0.0.0', port=1337, workers=4, debug=False, access_log=False)
+```
+
+Running via Gunicorn you can set `--log-level` higher than `info` to not get any access logs anymore.
+
+```
+gunicorn myapp:app --bind 0.0.0.0:1337 --worker-class sanic.worker.GunicornWorker --log-level warning
+```
+
 ## Asynchronous support
 This is suitable if you *need* to share the sanic process with other applications, in particular the `loop`.
 However be advised that this method does not support using multiple processes, and is not the preferred way