@Override
    protected void process(ClusterDistributionManager dm) {
      InitialImageFlowControl control = (InitialImageFlowControl) keeper.retrieve(keeperId);
      if (control != null) {
        control.releasePermit();
      }
    }
Return the time in sec to wait before sending an alert while waiting for ack replies. Note that
the ack wait threshold may change at runtime, so we have to consult the system every time.
geode-core/src/main/java/org/apache/geode/internal/cache/InitialImageFlowControl.java