gitlab: Make memory limits configurable

This patch adds two new variables to the gitlab playbook, making the
memory limits of the container configurable and this way easier to
adjust to one's needs.

roles/gitlab/defaults/main.yml

@@ -42,6 +42,13 @@ gitlab_version: 13.8.4-ce.0
 # The port you want Gitlab to listen on for SSH connections
 gitlab_ssh_port: 22
 
+# The memory limits for the GitLab container
+#
+# Notice the gitlab_memoryswap_limit must be equal
+# or higher than the gitlab_memory_limit
+gitlab_memory_limit: "4096mb"
+gitlab_memoryswap_limit: "4352mb"
+
 # Email/SMTP settings
 gitlab_smtp_address: smtp.example.com
 gitlab_smtp_port: 465

roles/gitlab/templates/docker-compose.yml

@@ -22,8 +22,8 @@ services:
   web:
     image: docker.io/gitlab/gitlab-ce:{{ gitlab_version }}
     hostname: '{{ gitlab_domain }}'
-    mem_limit: 4500mb
+    mem_limit: {{ gitlab_memory_limit }}
-    memswap_limit: 5000mb
+    memswap_limit: {{ gitlab_memoryswap_limit }}
     environment:
       GITLAB_OMNIBUS_CONFIG: |
         external_url 'https://{{ gitlab_domain }}'