Added open search settings

docs/get-started.md

@@ -47,6 +47,13 @@ and [`.env`](https://gitlab.phaidra.org/fair-data-austria-db-repository/fda-serv
     curl -o dbrepo.conf https://gitlab.phaidra.org/fair-data-austria-db-repository/fda-services/-/raw/master/dbrepo.conf
     curl -o .env https://gitlab.phaidra.org/fair-data-austria-db-repository/fda-services/-/raw/master/.env.unix.example
 
+Increase the virtual memory max swap limit for OpenSearch to at least 262144 on the *host machine* according
+to [the official manual](https://opensearch.org/docs/1.0/opensearch/install/important-settings/), you need *sudo*
+permissions for this (check first with `cat /proc/sys/vm/max_map_count`):
+
+    echo "vm.max_map_count=262144" >> /etc/sysctl.conf
+    sysctl -p
+
 Start the services:
 
     docker compose pull