@Override
  public double getWorkFactor() {
    return 1.0 / (workToIdleFactor + 1.0);
  }
Executes the given command on the current thread. If throttling is enabled (the work factor
is less than 1.0) this command may optionally insert a delay before returning to satisfy the
requested work factor.
<p>
This method will not operate correctly if used by more than one thread.

@param command the work to execute
samza-core/src/main/java/org/apache/samza/util/ThrottlingExecutor.java