subrouter.Methods(http.MethodPost).Path("/v1/force-unlock").HandlerFunc(lockServer.ForceUnlockHandler)

		nodes[i] = httptest.NewServer(router)
	}
}

const WriteLock = -1

type lockServer struct {
	mutex sync.Mutex
	// Map of locks, with negative value indicating (exclusive) write lock
	// and positive values indicating number of read locks
	lockMap map[string]int64

		WriteSectors: currentStats.WriteSectors - initialStats.WriteSectors,
		ReadTicks:    currentStats.ReadTicks - initialStats.ReadTicks,
		WriteTicks:   currentStats.WriteTicks - initialStats.WriteTicks,
		TotalTicks:   currentStats.TotalTicks - initialStats.TotalTicks,
	}
}

func getDriveIOStatMetrics(ioStats madmin.DiskIOStats, duration time.Duration) (m driveIOStatMetrics) {

				ReadIOs:        1432553,
				ReadMerges:     420084,
				ReadSectors:    66247626,
				ReadTicks:      2398227,
				WriteIOs:       7077314,
				WriteMerges:    8720147,
				WriteSectors:   157049224,
				WriteTicks:     7469810,
				CurrentIOs:     0,
				TotalTicks:     7580552,
				ReqTicks:       9869354,
				DiscardIOs:     46037,
				DiscardMerges:  0,
				DiscardSectors: 41695120,
				DiscardTicks:   1315,

				ReadSectors:    st.ReadSectors,
				ReadTicks:      st.ReadTicks,
				WriteIOs:       st.WriteIOs,
				WriteMerges:    st.WriteMerges,
				WriteSectors:   st.WriteSectors,
				WriteTicks:     st.WriteTicks,
				CurrentIOs:     st.CurrentIOs,
				TotalTicks:     st.TotalTicks,
				ReqTicks:       st.ReqTicks,
				DiscardIOs:     st.DiscardIOs,
				DiscardMerges:  st.DiscardMerges,

type IOStats struct {
	ReadIOs        uint64
	ReadMerges     uint64
	ReadSectors    uint64
	ReadTicks      uint64
	WriteIOs       uint64
	WriteMerges    uint64
	WriteSectors   uint64
	WriteTicks     uint64
	CurrentIOs     uint64
	TotalTicks     uint64
	ReqTicks       uint64
	DiscardIOs     uint64
	DiscardMerges  uint64
	DiscardSectors uint64
	DiscardTicks   uint64
	FlushIOs       uint64

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

	iostats = IOStats{
		ReadIOs:      stats[0],
		ReadMerges:   stats[1],
		ReadSectors:  stats[2],
		ReadTicks:    stats[3],
		WriteIOs:     stats[4],
		WriteMerges:  stats[5],
		WriteSectors: stats[6],
		WriteTicks:   stats[7],
		CurrentIOs:   stats[8],
		TotalTicks:   stats[9],
		ReqTicks:     stats[10],
	}
	// as per the doc, only 11 fields are guaranteed
	// only set if available
	if len(stats) > 14 {