Propose an explanation how to restart gracefully gitea after an update (#10866)

Co-authored-by: guillep2k <18600385+guillep2k@users.noreply.github.com>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lauris BH <lauris@nix.lv>

docs/content/doc/installation/from-binary.en-us.md

@@ -113,6 +113,18 @@ It is recommended you do a [backup]({{< relref "doc/usage/backup-and-restore.en-
 If you have carried out the installation steps as described above, the binary should
 have the generic name `gitea`. Do not change this, i.e. to include the version number.
 
+### 1. Restarting gitea with systemd (recommended)
+
+As explained before, we recommend to use systemd as service manager. In this case ```systemctl restart gitea``` should be enough.
+
+### 2. Restarting gitea without systemd
+
+To restart your gitea instance, we recommend to use SIGHUP signal. If you know your gitea PID use ```kill -1 $GITEA_PID``` otherwise you can use ```killall -1 gitea``` or ```pkill -1 gitea```
+
+To gracefully stop the gitea instance, a simple ```kill $GITEA_PID``` or ```killall gitea``` is enough.
+
+**NOTE:** We don't recommend to use SIGKILL signal (know also as `-9`), you may be forcefully stopping some of Gitea internal tasks and it will not gracefully stop (tasks in queues, indexers processes, etc.)
+
 See below for troubleshooting instructions to repair broken repositories after
 an update of your Gitea version.