@Before
  public void setUp() throws Exception {
    File testDir = temporaryFolder.getRoot();
    assertThat(testDir.exists()).isTrue();
    System.setProperty(SimpleStatSampler.ARCHIVE_FILE_NAME_PROPERTY, testDir.getAbsolutePath()
        + File.separator + SimpleStatSampler.DEFAULT_ARCHIVE_FILE_NAME);
    LinuxProcFsStatistics.init();
    initStats();
    StatisticsTypeImpl statisticsType = (StatisticsTypeImpl) LinuxSystemStats.getType();
    localStats = (LocalStatisticsImpl) getStatisticsManager()
        .createStatistics(statisticsType, statisticsType.getName());
  }
Technically a linux only test - the file handling is all mocked up so the test can run on any
host os.
geode-core/src/integrationTest/java/org/apache/geode/internal/statistics/LinuxSystemStatsTest.java