private long runBenchmark(Runnable[] runnable, final int numThreads) throws InterruptedException {
    Thread[] threads = new Thread[numThreads];
    long startTime = EnvironmentEdgeManager.currentTime();
    for (int i = 0; i < numThreads; ++i) {
      threads[i] =
        new Thread(runnable[i % runnable.length], "t" + i + ",r" + (i % runnable.length));
      threads[i].start();
    }
    for (Thread t : threads)
      t.join();
    long endTime = EnvironmentEdgeManager.currentTime();
    return (endTime - startTime);
  }
Verify the content of the WAL file. Verify that the file has expected number of edits.
@param wals may not be null
@return Count of edits.
hbase-diagnostics/src/main/java/org/apache/hadoop/hbase/wal/WALPerformanceEvaluation.java