/// <summary>
/// Remove nodes using copy on write semantics.
/// </summary>
private void RemoveNodesCopy(List <Node> nodesToRemove)
{
// Create temporary nodes array.
// Since nodes are only marked for deletion using node references in the nodes array,
// and the tend thread is the only thread modifying nodes, we are guaranteed that nodes
// in nodesToRemove exist. Therefore, we know the final array size.
Node[] nodeArray = new Node[nodes.Length - nodesToRemove.Count];
int count = 0;
// Add nodes that are not in remove list.
foreach (Node node in nodes)
{
if (FindNode(node, nodesToRemove))
{
if (tendValid && Log.InfoEnabled())
{
Log.Info("Remove node " + node);
}
}
else
{
nodeArray[count++] = node;
}
}
// Do sanity check to make sure assumptions are correct.
if (count < nodeArray.Length)
{
if (Log.WarnEnabled())
{
Log.Warn("Node remove mismatch. Expected " + nodeArray.Length + " Received " + count);
}
// Resize array.
Node[] nodeArray2 = new Node[count];
Array.Copy(nodeArray, 0, nodeArray2, 0, count);
nodeArray = nodeArray2;
}
hasPartitionScan = Cluster.SupportsPartitionScan(nodeArray);
// Replace nodes with copy.
nodes = nodeArray;
}
/// <summary>
/// Add nodes using copy on write semantics.
/// </summary>
private void AddNodes(Dictionary <string, Node> nodesToAdd)
{
// Add all nodes at once to avoid copying entire array multiple times.
// Create temporary nodes array.
Node[] nodeArray = new Node[nodes.Length + nodesToAdd.Count];
int count = 0;
// Add existing nodes.
foreach (Node node in nodes)
{
nodeArray[count++] = node;
}
// Add new nodes
foreach (Node node in nodesToAdd.Values)
{
if (Log.InfoEnabled())
{
Log.Info("Add node " + node);
}
nodeArray[count++] = node;
nodesMap[node.Name] = node;
// Add node's aliases to global alias set.
// Aliases are only used in tend thread, so synchronization is not necessary.
foreach (Host alias in node.aliases)
{
aliases[alias] = node;
}
}
hasPartitionScan = Cluster.SupportsPartitionScan(nodeArray);
// Replace nodes with copy.
nodes = nodeArray;
}