/// <summary>DatanodeDescriptor constructor</summary>
/// <param name="nodeID">id of the data node</param>
public DatanodeDescriptor(DatanodeID nodeID)
: base(nodeID)
{
decommissioningStatus = new DatanodeDescriptor.DecommissioningStatus(this);
pendingCached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.PendingCached);
cached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.Cached);
pendingUncached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.PendingUncached);
// isAlive == heartbeats.contains(this)
// This is an optimization, because contains takes O(n) time on Arraylist
// A system administrator can tune the balancer bandwidth parameter
// (dfs.balance.bandwidthPerSec) dynamically by calling
// "dfsadmin -setBalanacerBandwidth <newbandwidth>", at which point the
// following 'bandwidth' variable gets updated with the new value for each
// node. Once the heartbeat command is issued to update the value on the
// specified datanode, this value will be set back to 0.
/* Variables for maintaining number of blocks scheduled to be written to
* this storage. This count is approximate and might be slightly bigger
* in case of errors (e.g. datanode does not report if an error occurs
* while writing the block).
*/
//10min
// The number of replication work pending before targets are determined
// HB processing can use it to tell if it is the first HB since DN restarted
UpdateHeartbeatState(StorageReport.EmptyArray, 0L, 0L, 0, 0, null);
}
/// <summary>DatanodeDescriptor constructor</summary>
/// <param name="nodeID">id of the data node</param>
/// <param name="networkLocation">location of the data node in network</param>
public DatanodeDescriptor(DatanodeID nodeID, string networkLocation)
: base(nodeID, networkLocation)
{
decommissioningStatus = new DatanodeDescriptor.DecommissioningStatus(this);
pendingCached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.PendingCached);
cached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.Cached);
pendingUncached = new DatanodeDescriptor.CachedBlocksList(this, DatanodeDescriptor.CachedBlocksList.Type
.PendingUncached);
UpdateHeartbeatState(StorageReport.EmptyArray, 0L, 0L, 0, 0, null);
}