How to change Xmx settings for sonar runner?
You can simply put a sonar.properties file under /opt/docker-sonar/conf/. This file will be available inside the container under /opt/sonarqube/conf/, because the folder gets mounted as volume.
A full example for a sonar.properties file can be found on github. However all you need to enter is:
sonar.ce.javaOpts=-Xmx&lt;XMX_VALUE -Xms&lt;XMS_VALUE&gt; -XX:+HeapDumpOnOutOfMemoryError