public virtual void TestChooseReplicaToDelete()
{
MiniDFSCluster cluster = null;
FileSystem fs = null;
try
{
Configuration conf = new HdfsConfiguration();
conf.SetLong(DFSConfigKeys.DfsBlockSizeKey, SmallBlockSize);
cluster = new MiniDFSCluster.Builder(conf).NumDataNodes(3).Build();
fs = cluster.GetFileSystem();
FSNamesystem namesystem = cluster.GetNamesystem();
conf.SetLong(DFSConfigKeys.DfsHeartbeatIntervalKey, 300);
cluster.StartDataNodes(conf, 1, true, null, null, null);
DataNode lastDN = cluster.GetDataNodes()[3];
DatanodeRegistration dnReg = DataNodeTestUtils.GetDNRegistrationForBP(lastDN, namesystem
.GetBlockPoolId());
string lastDNid = dnReg.GetDatanodeUuid();
Path fileName = new Path("/foo2");
DFSTestUtil.CreateFile(fs, fileName, SmallFileLength, (short)4, 0L);
DFSTestUtil.WaitReplication(fs, fileName, (short)4);
// Wait for tolerable number of heartbeats plus one
DatanodeDescriptor nodeInfo = null;
long lastHeartbeat = 0;
long waitTime = DFSConfigKeys.DfsHeartbeatIntervalDefault * 1000 * (DFSConfigKeys
.DfsNamenodeTolerateHeartbeatMultiplierDefault + 1);
do
{
nodeInfo = namesystem.GetBlockManager().GetDatanodeManager().GetDatanode(dnReg);
lastHeartbeat = nodeInfo.GetLastUpdateMonotonic();
}while (Time.MonotonicNow() - lastHeartbeat < waitTime);
fs.SetReplication(fileName, (short)3);
BlockLocation[] locs = fs.GetFileBlockLocations(fs.GetFileStatus(fileName), 0, long.MaxValue
);
// All replicas for deletion should be scheduled on lastDN.
// And should not actually be deleted, because lastDN does not heartbeat.
namesystem.ReadLock();
ICollection <Block> dnBlocks = namesystem.GetBlockManager().excessReplicateMap[lastDNid
];
NUnit.Framework.Assert.AreEqual("Replicas on node " + lastDNid + " should have been deleted"
, SmallFileLength / SmallBlockSize, dnBlocks.Count);
namesystem.ReadUnlock();
foreach (BlockLocation location in locs)
{
NUnit.Framework.Assert.AreEqual("Block should still have 4 replicas", 4, location
.GetNames().Length);
}
}
finally
{
if (fs != null)
{
fs.Close();
}
if (cluster != null)
{
cluster.Shutdown();
}
}
}