private void validateBackupComplete() {
    Pattern pattern = Pattern.compile(".*INCOMPLETE.*");
    File[] files = backupBaseDir.listFiles((dir, name) -> pattern.matcher(name).matches());

    assertThat(files).isNotNull().hasSize(0);
  }
Test what happens when we restart persistent members while there is an accessor concurrently
performing puts.
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/backup/BackupDistributedTest.java