private void clearShadowBucketRegions(PartitionedRegion shadowRegion) {
    PartitionedRegionDataStore.BucketVisitor bucketVisitor =
        (bucketId, r) -> ((BucketRegion) r).clearEntries(null);

    shadowRegion.getDataStore().visitBuckets(bucketVisitor);
  }
Put entries in region after gateway sender is stopped. Count number of PQRM messages sent.
geode-wan/src/distributedTest/java/org/apache/geode/internal/cache/wan/parallel/ParallelGatewaySenderOperationsDistributedTest.java