/// <summary>
/// Checks whether specified cache entry is still valid, based on Affinity Topology Version.
/// When primary node changes for a key, GridNearCacheEntry stops receiving updates for that key,
/// because reader ("subscription") on new primary is not yet established.
/// <para />
/// This method is similar to GridNearCacheEntry.valid().
/// </summary>
/// <param name="entry">Entry to validate.</param>
/// <typeparam name="TVal">Value type.</typeparam>
/// <returns>True if entry is valid and can be returned to the user; false otherwise.</returns>
private bool IsValid <TVal>(NearCacheEntry <TVal> entry)
{
// See comments on _affinityTopologyVersionFunc about boxed copy approach.
var currentVerBoxed = _affinityTopologyVersionFunc();
var entryVerBoxed = entry.Version;
Debug.Assert(currentVerBoxed != null);
if (ReferenceEquals(currentVerBoxed, entryVerBoxed))
{
// Happy path: true on stable topology.
return(true);
}
if (entryVerBoxed == null)
{
return(false);
}
var entryVer = (AffinityTopologyVersion)entryVerBoxed;
var currentVer = (AffinityTopologyVersion)currentVerBoxed;
if (entryVer >= currentVer)
{
return(true);
}
var part = entry.Partition;
var valid = _affinity.IsAssignmentValid(entryVer, part);
// Update version or mark as invalid (null).
entry.CompareExchangeVersion(valid ? currentVerBoxed : null, entryVerBoxed);
return(valid);
}
/** <inheritdoc /> */
public void Update(IBinaryStream stream, Marshaller marshaller)
{
Debug.Assert(stream != null);
Debug.Assert(marshaller != null);
if (_stopped)
{
return;
}
var mode = _keepBinary ? BinaryMode.ForceBinary : BinaryMode.Deserialize;
var reader = marshaller.StartUnmarshal(stream, mode);
var key = reader.ReadObject <TK>();
var hasVal = stream.ReadBool();
if (hasVal)
{
var val = reader.ReadObject <TV>();
var part = stream.ReadInt();
var ver = new AffinityTopologyVersion(stream.ReadLong(), stream.ReadInt());
_map[key] = new NearCacheEntry <TV>(val, GetBoxedAffinityTopologyVersion(ver), part);
}
else
{
NearCacheEntry <TV> unused;
_map.TryRemove(key, out unused);
}
}
