add section on profiling synse server

docs/server/developer/debugging.md

@@ -35,3 +35,45 @@ stdout/stderr, so they can be accessed via `docker logs`, e.g.
 ```
 docker logs synse-server
 ```
+
+## Profiling
+
+As of Synse Server version `v3.0.1`, a `--profile` flag is made available to run Synse Server in
+profiling mode. This uses [cProfile](https://docs.python.org/3/library/profile.html#module-cProfile)
+to gather the profiling data. When the flag is set, profiling data will be printed out to console and
+written out to file (synse-server.profile).
+
+To set the flag, pass `--profile` in as a command to the container, e.g.
+
+```
+docker run vaporio/synse-server --profile
+```
+
+or, in a compose file
+
+```yaml
+version: '3'
+services:
+  synse-server:
+    image: vaporio/synse-server
+    ports:
+    - '5000:5000'
+    command: ['--profile']
+```
+
+To get the profiling data, stop synse server (e.g. `docker stop synse-server`). You can view the
+profiling data by:
+
+- looking at the container logs (`docker logs synse-server`)
+- copying the profile out of the container (`docker cp synse-server:/synse/synse-server.profile .`)
+
+From there, you can use tools like [`gprof2dot`](https://github.com/jrfonseca/gprof2dot) and
+[`dot`](https://github.com/pydot/pydot) to create graphs of the data, or write a simple script
+to parse the profiling data as desired.
+
+For example:
+
+```bash
+$ gprof2dot -f pstats synse-server.profile -o synse-server.dot
+$ dot -Tpng synse-server.dot -o synse-server.png
+```