[docs] Updates for DB, swap and HTTP/2 on nginx (#2547)

* [docs] Add warning about DBs on network storage

* [docs] Mention tuning swappiness on Linux

* [docs] Mention enabling HTTP/2 on nginx

docs/getting_started/reverse_proxy/nginx.md

@@ -2,6 +2,9 @@
 
 In order to use NGINX as a reverse proxy for GoToSocial you'll need to have it installed on your server. If you intend for the NGINX instance to also handle TLS, you'll need to [provision TLS certificates](../../advanced/certificates.md) too.
 
+!!! tip
+    Enable HTTP/2 in nginx by including `http2` in the `listen` directives. This can speed up the experience for clients. Browsers do not support HTTP/2 over plain text, so this should only be added to `listen` directives for port `443` that also include the `ssl` directive.
+
 NGINX is [packaged for many distributions](https://repology.org/project/nginx/versions). It's very likely you can install it with your distribution's package manager. You can also run NGINX using a container runtime with the [official NGINX image](https://hub.docker.com/_/nginx) that's published to the Docker Hub.
 
 In this guide we'll also show how to use certbot to provision the TLS certificates. It too is [packaged in many distributions](https://repology.org/project/certbot/versions) but many distributions tend to ship fairly old versions of certbot. If you run into trouble it may be worth considering using the [container image](https://hub.docker.com/r/certbot/certbot) instead.
@@ -159,8 +162,8 @@ server {
   }
   client_max_body_size 40M;
 
-  listen [::]:443 ssl ipv6only=on; # managed by Certbot
-  listen 443 ssl; # managed by Certbot
+  listen [::]:443 ssl ipv6only=on http2; # managed by Certbot
+  listen 443 ssl http2; # managed by Certbot
   ssl_certificate /etc/letsencrypt/live/example.org/fullchain.pem; # managed by Certbot
   ssl_certificate_key /etc/letsencrypt/live/example.org/privkey.pem; # managed by Certbot
   include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot