@Test
  public void testParallelPropagationSenderResume() throws Exception {
    Integer lnPort = vm0.invoke(() -> WANTestBase.createFirstLocatorWithDSId(1));
    Integer nyPort = vm1.invoke(() -> WANTestBase.createFirstRemoteLocator(2, lnPort));

    createCacheInVMs(nyPort, vm2, vm3);
    createReceiverInVMs(vm2, vm3);

    createCacheInVMs(lnPort, vm4, vm5, vm6, vm7);

    vm4.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 8, OrderPolicy.KEY));
    vm5.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 8, OrderPolicy.KEY));
    vm6.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 8, OrderPolicy.KEY));
    vm7.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 8, OrderPolicy.KEY));

    vm4.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 1, 100,
        isOffHeap()));
    vm5.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 1, 100,
        isOffHeap()));
    vm6.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 1, 100,
        isOffHeap()));
    vm7.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 1, 100,
        isOffHeap()));

    startSenderInVMs("ln", vm4, vm5, vm6, vm7);

    vm2.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", null, 1, 100,
        isOffHeap()));
    vm3.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", null, 1, 100,
        isOffHeap()));

    // make sure all the senders are running before doing any puts
    vm4.invoke(() -> WANTestBase.waitForSenderRunningState("ln"));
    vm5.invoke(() -> WANTestBase.waitForSenderRunningState("ln"));
    vm6.invoke(() -> WANTestBase.waitForSenderRunningState("ln"));
    vm7.invoke(() -> WANTestBase.waitForSenderRunningState("ln"));

    // now, the senders are started. So, start the puts
    vm4.invokeAsync(() -> WANTestBase.doPuts(getTestMethodName() + "_PR", 1000));

    // now, pause all of the senders
    vm4.invoke(() -> WANTestBase.pauseSender("ln"));
    vm5.invoke(() -> WANTestBase.pauseSender("ln"));
    vm6.invoke(() -> WANTestBase.pauseSender("ln"));
    vm7.invoke(() -> WANTestBase.pauseSender("ln"));

    // sleep for a second or two
    Wait.pause(2000);

    // resume the senders
    vm4.invoke(() -> WANTestBase.resumeSender("ln"));
    vm5.invoke(() -> WANTestBase.resumeSender("ln"));
    vm6.invoke(() -> WANTestBase.resumeSender("ln"));
    vm7.invoke(() -> WANTestBase.resumeSender("ln"));

    Wait.pause(2000);

    vm4.invoke(() -> WANTestBase.validateParallelSenderQueueAllBucketsDrained("ln"));
    vm5.invoke(() -> WANTestBase.validateParallelSenderQueueAllBucketsDrained("ln"));
    vm6.invoke(() -> WANTestBase.validateParallelSenderQueueAllBucketsDrained("ln"));
    vm7.invoke(() -> WANTestBase.validateParallelSenderQueueAllBucketsDrained("ln"));

    // find the region size on remote vm
    vm2.invoke(() -> WANTestBase.validateRegionSize(getTestMethodName() + "_PR", 1000));

  }
Normal scenario in which a paused sender is resumed.
geode-wan/src/distributedTest/java/org/apache/geode/internal/cache/wan/concurrent/ConcurrentParallelGatewaySenderOperation_1_DUnitTest.java