presto-main/src/main/java/io/prestosql/execution/resourcegroups/InternalResourceGroup.java/InternalResourceGroup/updateGroupsAndProcessQueuedQueries
class InternalResourceGroup:        public synchronized void updateGroupsAndProcessQueuedQueries()
        {
            updateResourceUsageAndGetDelta();

            while (internalStartNext()) {
                // start all the queries we can
            }
        }