Update documentation

docs/docs/testing-and-debugging/pprof.md

@@ -1,19 +1,61 @@
-# Pprof
+---
+layout: default
+title: Pprof
+permalink: /testing-and-debugging/pprof
+---
 
-There is a built pprof server to faciliate profiling the program.
+## Pprof
+
+There is a built-in pprof server to faciliate profiling the program.
+You can enable it with the flag `--pprofserver` or by modifying the TOML configuration file.
 
 Note it does not affect performance unless the server is queried.
 
 We assume Gossamer runs on `localhost` and the Pprof server is listening
-on the default `6060` port.
+on the default `6060` port. You can configure the Pprof server listening address with the pprof TOML key `listening-address` or the flag `--pprofaddress`.
 
 You need to have [Go](https://golang.org/dl/) installed to profile the program.
 
+### Browser
+
 The easiest way to visualize profiling data is through your browser.
 
-The following commands are available and will show the result at [http://localhost:8000](http://localhost:8000):
+For example, the following commands will show interactive results at [http://localhost:8000](http://localhost:8000):
 
 ```sh
 # Check the heap
 go tool pprof -http=localhost:8000 http://localhost:6060/debug/pprof/heap
+# Check the CPU time spent for 10 seconds
+go tool pprof -http=localhost:8000 http://localhost:6060/debug/pprof/profile?seconds=10
 ```
+
+### Compare heaps
+
+You can compare heaps with Go's pprof, this is especially useful to find memory leaks.
+
+1. Download the first heap profile `wget -qO heap.1.out http://localhost:6060/debug/pprof/heap`
+1. Download the second heap profile `wget -qO heap.2.out http://localhost:6060/debug/pprof/heap`
+1. Compare the second heap profile with the first one using `go tool pprof -base ./heap.1.out heap.2.out`
+
+### More routes
+
+More routes are available in the HTTP pprof server. You can also list them at [http://localhost:6060/debug/pprof/](http://localhost:6060/debug/pprof/).
+Notable ones are written below:
+
+#### Goroutine blocking profile
+
+The route `/debug/pprof/block` is available but requires to set the block profile rate, using either the toml value `block-rate` or the flag `--pprofblockrate`.
+
+#### Mutex contention profile
+
+The route `/debug/pprof/mutex` is available but requires to set the mutex profile rate, using either the toml value `mutex-rate` or the flag `--pprofmutexrate`.
+
+#### Other routes
+
+The other routes are listed below, if you need them:
+
+- `/debug/pprof/cmdline`
+- `/debug/pprof/symbol`
+- `/debug/pprof/trace`
+- `/debug/pprof/goroutine`
+- `/debug/pprof/threadcreate`