/// <summary>Register a slot.</summary>
/// <remarks>
/// Register a slot.
/// This function looks at a slot which has already been initialized (by
/// another process), and registers it with us. Then, it returns the
/// relevant Slot object.
/// </remarks>
/// <returns>The slot.</returns>
/// <exception cref="Org.Apache.Hadoop.FS.InvalidRequestException">
/// If the slot index we're trying to allocate has not been
/// initialized, or is already in use.
/// </exception>
public ShortCircuitShm.Slot RegisterSlot(int slotIdx, ExtendedBlockId blockId)
{
lock (this)
{
if (slotIdx < 0)
{
throw new InvalidRequestException(this + ": invalid negative slot " + "index " +
slotIdx);
}
if (slotIdx >= slots.Length)
{
throw new InvalidRequestException(this + ": invalid slot " + "index " + slotIdx);
}
if (allocatedSlots.Get(slotIdx))
{
throw new InvalidRequestException(this + ": slot " + slotIdx + " is already in use."
);
}
ShortCircuitShm.Slot slot = new ShortCircuitShm.Slot(this, CalculateSlotAddress(slotIdx
), blockId);
if (!slot.IsValid())
{
throw new InvalidRequestException(this + ": slot " + slotIdx + " is not marked as valid."
);
}
slots[slotIdx] = slot;
allocatedSlots.Set(slotIdx, true);
if (Log.IsTraceEnabled())
{
Log.Trace(this + ": registerSlot " + slotIdx + ": allocatedSlots=" + allocatedSlots
+ StringUtils.GetStackTrace(Sharpen.Thread.CurrentThread()));
}
return(slot);
}
}
/// <exception cref="System.IO.IOException"/>
public void Visit(Dictionary <DatanodeInfo, DfsClientShmManager.PerDatanodeVisitorInfo
> info)
{
NUnit.Framework.Assert.IsTrue(info[datanode].full.IsEmpty());
NUnit.Framework.Assert.IsFalse(info[datanode].disabled);
NUnit.Framework.Assert.AreEqual(1, info[datanode].notFull.Values.Count);
DfsClientShm shm = info[datanode].notFull.Values.GetEnumerator().Next();
for (IEnumerator <ShortCircuitShm.Slot> iter = shm.SlotIterator(); iter.HasNext();)
{
ShortCircuitShm.Slot slot = iter.Next();
if (slot.IsValid())
{
this._enclosing.done.SetValue(false);
}
}
}
/// <summary>Check if the replica is stale.</summary>
/// <remarks>
/// Check if the replica is stale.
/// Must be called with the cache lock held.
/// </remarks>
internal virtual bool IsStale()
{
if (slot != null)
{
// Check staleness by looking at the shared memory area we use to
// communicate with the DataNode.
bool stale = !slot.IsValid();
if (Log.IsTraceEnabled())
{
Log.Trace(this + ": checked shared memory segment. isStale=" + stale);
}
return(stale);
}
else
{
// Fall back to old, time-based staleness method.
long deltaMs = Time.MonotonicNow() - creationTimeMs;
long staleThresholdMs = cache.GetStaleThresholdMs();
if (deltaMs > staleThresholdMs)
{
if (Log.IsTraceEnabled())
{
Log.Trace(this + " is stale because it's " + deltaMs + " ms old, and staleThresholdMs = "
+ staleThresholdMs);
}
return(true);
}
else
{
if (Log.IsTraceEnabled())
{
Log.Trace(this + " is not stale because it's only " + deltaMs + " ms old, and staleThresholdMs = "
+ staleThresholdMs);
}
return(false);
}
}
}