public virtual void TestTriggerBlockIdCollision()
{
Configuration conf = new HdfsConfiguration();
conf.SetInt(DFSConfigKeys.DfsReplicationKey, 1);
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).NumDataNodes(1).Build();
try
{
cluster.WaitActive();
FileSystem fs = cluster.GetFileSystem();
FSNamesystem fsn = cluster.GetNamesystem();
int blockCount = 10;
// Create a file with a few blocks to rev up the global block ID
// counter.
Path path1 = new Path("testBlockIdCollisionDetection_file1.dat");
DFSTestUtil.CreateFile(fs, path1, IoSize, BlockSize * blockCount, BlockSize, Replication
, Seed);
IList <LocatedBlock> blocks1 = DFSTestUtil.GetAllBlocks(fs, path1);
// Rewind the block ID counter in the name system object. This will result
// in block ID collisions when we try to allocate new blocks.
SequentialBlockIdGenerator blockIdGenerator = fsn.GetBlockIdManager().GetBlockIdGenerator
();
blockIdGenerator.SetCurrentValue(blockIdGenerator.GetCurrentValue() - 5);
// Trigger collisions by creating a new file.
Path path2 = new Path("testBlockIdCollisionDetection_file2.dat");
DFSTestUtil.CreateFile(fs, path2, IoSize, BlockSize * blockCount, BlockSize, Replication
, Seed);
IList <LocatedBlock> blocks2 = DFSTestUtil.GetAllBlocks(fs, path2);
Assert.AssertThat(blocks2.Count, CoreMatchers.Is(blockCount));
// Make sure that file2 block IDs start immediately after file1
Assert.AssertThat(blocks2[0].GetBlock().GetBlockId(), CoreMatchers.Is(blocks1[9].
GetBlock().GetBlockId() + 1));
}
finally
{
cluster.Shutdown();
}
}
public BlockIdManager(BlockManager blockManager)
{
this.generationStampV1Limit = GenerationStamp.GrandfatherGenerationStamp;
this.blockIdGenerator = new SequentialBlockIdGenerator(blockManager);
}
