How to add more Talkyard server RAM

If you're self hosted, some day you might need to add more server memory (RAM), typically to the Talkyard application server.

How to add application server memory

Do this:

1. Increase the amount of memory available to the server (e.g. a Virtual Private Server, VPS). E.g. edit the server config in your cloud provider's admin panel.

2. As root, verify that there's more memory available:

   $ sudo -i
   # free -m   # -m means megabytes
   

3. Edit /opt/talkyard/docker-compose.override.yml and tell the Talkyard application server to make use of this memory: (otherwise it'll think it's for PostgreSQL's file cache or ElasticSearch or something else)

   ...
   services:
     app:
       environment:
         PLAY_HEAP_MEMORY_MB: NNNN  <—— change this
   ...
   

4. Recreate the application server Docker container, to make the changes take effect: (this is easy to forget)

   docker-compose stop app     # stops the app server
   docker-compose rm -f app    # removes the app server container
   docker-compose up -d app    # recreates the container — with the new memory settings
   
   # And check that it starts up properly:
   docker-compose logs -f app
   

Now the app server has more memory.

Verify that it worked

If you'd like to check that the changes have indeed taken effect, you can, as root:

## jump into the app server container:
root# cd /opt/talkyard/
root# docker-compose exec app bash

## Now you're in a shell in the app server container.
## Check  the free memory — the 'total' column matches the total server RAM in MB:
bash-4.4# free -m
             total       used       free     shared    buffers     cached
Mem:          7962       4942       3019        140         69       1120
-/+ buffers/cache:       3752       4210
Swap:            0          0          0

And verify that the app server was started with the new memory configuration; -Xms2200m should match PLAY_HEAP_MEMORY_MB.

bash-4.4# ps aux  
PID   USER     TIME  COMMAND
    1 root      0:06 /usr/lib/jvm/java-1.8-openjdk/bin/java -Duser.dir=/opt/talkyard/app -Xms2200m -Xmx2200m ...
   78 root      0:00 bash
   89 root      0:00 ps aux

If -Xms ... is wrong, you might have forgotten step 3 or 4 above, i.e. to edit the config file, and to recreate the app server.