Author: todd Date: Thu Nov 3 01:00:25 2011 New Revision: 1196902 URL: http://svn.apache.org/viewvc?rev=1196902&view=rev Log: HDFS-2533. Remove needless synchronization on some FSDataSet methods. Contributed by Todd Lipcon.
Modified: hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java Modified: hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt URL: http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt?rev=1196902&r1=1196901&r2=1196902&view=diff ============================================================================== --- hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt (original) +++ hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt Thu Nov 3 01:00:25 2011 @@ -877,6 +877,9 @@ Release 0.23.0 - 2011-11-01 HDFS-2130. Switch default checksum to CRC32C. (todd) + HDFS-2533. Remove needless synchronization on some FSDataSet methods. + (todd) + BUG FIXES HDFS-2347. Fix checkpointTxnCount's comment about editlog size. Modified: hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java URL: http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java?rev=1196902&r1=1196901&r2=1196902&view=diff ============================================================================== --- hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java (original) +++ hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java Thu Nov 3 01:00:25 2011 @@ -1258,7 +1258,7 @@ public class FSDataset implements FSData /** * Get File name for a given block. */ - public synchronized File getBlockFile(String bpid, Block b) + public File getBlockFile(String bpid, Block b) throws IOException { File f = validateBlockFile(bpid, b); if(f == null) { @@ -1271,16 +1271,44 @@ public class FSDataset implements FSData } @Override // FSDatasetInterface - public synchronized InputStream getBlockInputStream(ExtendedBlock b) + public InputStream getBlockInputStream(ExtendedBlock b) throws IOException { - return new FileInputStream(getBlockFile(b)); + File f = getBlockFileNoExistsCheck(b); + try { + return new FileInputStream(f); + } catch (FileNotFoundException fnfe) { + throw new IOException("Block " + b + " is not valid. " + + "Expected block file at " + f + " does not exist."); + } + } + + /** + * Return the File associated with a block, without first + * checking that it exists. This should be used when the + * next operation is going to open the file for read anyway, + * and thus the exists check is redundant. + */ + private File getBlockFileNoExistsCheck(ExtendedBlock b) + throws IOException { + File f = getFile(b.getBlockPoolId(), b.getLocalBlock()); + if (f == null) { + throw new IOException("Block " + b + " is not valid"); + } + return f; } @Override // FSDatasetInterface - public synchronized InputStream getBlockInputStream(ExtendedBlock b, + public InputStream getBlockInputStream(ExtendedBlock b, long seekOffset) throws IOException { - File blockFile = getBlockFile(b); - RandomAccessFile blockInFile = new RandomAccessFile(blockFile, "r"); + File blockFile = getBlockFileNoExistsCheck(b); + RandomAccessFile blockInFile; + try { + blockInFile = new RandomAccessFile(blockFile, "r"); + } catch (FileNotFoundException fnfe) { + throw new IOException("Block " + b + " is not valid. " + + "Expected block file at " + blockFile + " does not exist."); + } + if (seekOffset > 0) { blockInFile.seek(seekOffset); }