add notes for docker

docker/tricks.md

@@ -0,0 +1,43 @@
+## useful tricks for docker
+
+<br>
+
+
+#### shared folders
+
+Removing some of the default shared folders can decrease CPU usage (e.g. remove `/Volumes` and `/private`). 
+
+Check storage with:
+
+```
+docker info |grep Storage
+```
+
+
+<br>
+
+#### performance
+
+In case of performance problems you can run:
+
+```
+docker run --rm=true -it --privileged --pid=host \
+    <image name> /usr/bin/top
+```
+
+<br>
+
+#### cleaning up
+
+See disk space:
+
+```
+docker system df
+```
+
+
+Remove stopped containers, dangling images, the build cache, and unused networks:
+
+```
+docker system prune
+```