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

    createCacheInVMs(nyPort, vm2);
    vm2.invoke(WANTestBase::createReceiver);

    createCacheInVMs(lnPort, vm3, vm4);

    vm3.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 5, OrderPolicy.KEY));
    vm4.invoke(() -> WANTestBase.createConcurrentSender("ln", 2, true, 100, 10, false, false, null,
        true, 5, OrderPolicy.KEY));

    vm2.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", null, 0, 2,
        isOffHeap()));

    vm3.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 0, 2,
        isOffHeap()));
    vm4.invoke(() -> WANTestBase.createPartitionedRegion(getTestMethodName() + "_PR", "ln", 0, 2,
        isOffHeap()));

    startSenderInVMs("ln", vm3, vm4);

    vm3.invoke(() -> WANTestBase.doPutsPDXSerializable(getTestMethodName() + "_PR", 10));

    vm2.invoke(() -> WANTestBase.validateRegionSize_PDX(getTestMethodName() + "_PR", 10));
  }
Data is sent to all members containing the Partitioned Region when senders are killed.

Setup:
vm0 - locator with DSID=1 - on lnPort
vm1 - remote locator with DSID=2 - on nyPort - connected to lnPort
vm2-3 - server with cache connected to nyPort - has partitionedRegion w/o sender - has receiver
vm4-7 - server with cache connected to lnPort - has partitionedRegion w/ ln sender - has sender

Test:
1. Put 5000 entries to VM7 (async)
2. Assert that VM2 received at least 10 entries from VM7 through the sender (sync)
3. Kill sender on VM4 (async)
4. Get number of entries from VM2 (sync)
5. Put 10000 entries to VM6, with the first 5000 entries having the same keys as in the first
round of puts (async)
6. Assert that VM2 has twenty more entries than it did before puts on VM6 were started (sync)
7. Kill sender on VM5 (async)
8. Wait for previously started async invocations to complete
9. Assert that VM2, VM3, VM6, and VM7 all have 10000 entries
10. Assert that the sender queues on VM6 and VM7 are empty
geode-wan/src/distributedTest/java/org/apache/geode/internal/cache/wan/concurrent/ConcurrentParallelGatewaySenderDistributedTest.java