server/src/main/java/com/orientechnologies/orient/server/distributed/ODistributedConfiguration.java
public Boolean isExecutionModeSynchronous(final String iClusterName) {
    Object value = getClusterConfiguration(iClusterName).field(EXECUTION_MODE);
    if (value == null) {
      value = configuration.field(EXECUTION_MODE);
      if (value == null)
        return null;
    }

    if (value.toString().equalsIgnoreCase("undefined"))
      return null;

    return value.toString().equalsIgnoreCase(EXECUTION_MODE_SYNCHRONOUS);
  }
public Boolean isExecutionModeSynchronous(final String iClusterName) {
    Object value = getClusterConfiguration(iClusterName).field(EXECUTION_MODE);
    if (value == null) {
      value = configuration.field(EXECUTION_MODE);
      if (value == null)
        return null;
    }

    if (value.toString().equalsIgnoreCase("undefined"))
      return null;

    return value.toString().equalsIgnoreCase(EXECUTION_MODE_SYNCHRONOUS);
  }
Returns the execution mode if synchronous.

@param iClusterName Cluster name, or null for *

@return true = synchronous, false = asynchronous, null = undefined