private void backupDisk() throws IOException {

    File tmpDir = new File(dirs[0].getParent(), "backupDir");
    tmpDir.mkdirs();
    for (File file : dirs) {
      FileUtils.copyDirectory(file, new File(tmpDir, file.getName()));
    }
  }
Validate that values are, or are not, in memory
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/DiskRegionAsyncRecoveryJUnitTest.java