HDFS-7495. Remove updatePosition argument from DFSInputStream#getBlockAt() (cmccabe)

This commit is contained in:
Colin Patrick Mccabe 2015-02-25 13:29:31 -08:00
parent 5731c0e0d0
commit caa42adf20
2 changed files with 16 additions and 20 deletions

View File

@ -668,6 +668,9 @@ Release 2.7.0 - UNRELEASED
HDFS-7740. Test truncate with DataNodes restarting. (yliu)
HDFS-7495. Remove updatePosition argument from DFSInputStream#getBlockAt()
(cmccabe)
OPTIMIZATIONS
HDFS-7454. Reduce memory footprint for AclEntries in NameNode.

View File

@ -434,12 +434,10 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
* Fetch it from the namenode if not cached.
*
* @param offset block corresponding to this offset in file is returned
* @param updatePosition whether to update current position
* @return located block
* @throws IOException
*/
private LocatedBlock getBlockAt(long offset,
boolean updatePosition) throws IOException {
private LocatedBlock getBlockAt(long offset) throws IOException {
synchronized(infoLock) {
assert (locatedBlocks != null) : "locatedBlocks is null";
@ -449,7 +447,6 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
if (offset < 0 || offset >= getFileLength()) {
throw new IOException("offset < 0 || offset >= getFileLength(), offset="
+ offset
+ ", updatePosition=" + updatePosition
+ ", locatedBlocks=" + locatedBlocks);
}
else if (offset >= locatedBlocks.getFileLength()) {
@ -470,17 +467,6 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
}
blk = locatedBlocks.get(targetBlockIdx);
}
// update current position
if (updatePosition) {
// synchronized not strictly needed, since we only get here
// from synchronized caller methods
synchronized(this) {
pos = offset;
blockEnd = blk.getStartOffset() + blk.getBlockSize() - 1;
currentLocatedBlock = blk;
}
}
return blk;
}
}
@ -604,7 +590,14 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
//
// Compute desired block
//
LocatedBlock targetBlock = getBlockAt(target, true);
LocatedBlock targetBlock = getBlockAt(target);
// update current position
this.pos = target;
this.blockEnd = targetBlock.getStartOffset() +
targetBlock.getBlockSize() - 1;
this.currentLocatedBlock = targetBlock;
assert (target==pos) : "Wrong postion " + pos + " expect " + target;
long offsetIntoBlock = target - targetBlock.getStartOffset();
@ -979,7 +972,7 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
}
deadNodes.clear(); //2nd option is to remove only nodes[blockId]
openInfo();
block = getBlockAt(block.getStartOffset(), false);
block = getBlockAt(block.getStartOffset());
failures++;
continue;
}
@ -1056,7 +1049,7 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
byte[] buf, int offset,
Map<ExtendedBlock, Set<DatanodeInfo>> corruptedBlockMap)
throws IOException {
block = getBlockAt(block.getStartOffset(), false);
block = getBlockAt(block.getStartOffset());
while (true) {
DNAddrPair addressPair = chooseDataNode(block, null);
try {
@ -1108,7 +1101,7 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
// start of the loop.
CachingStrategy curCachingStrategy;
boolean allowShortCircuitLocalReads;
block = getBlockAt(block.getStartOffset(), false);
block = getBlockAt(block.getStartOffset());
synchronized(infoLock) {
curCachingStrategy = cachingStrategy;
allowShortCircuitLocalReads = !shortCircuitForbidden();
@ -1208,7 +1201,7 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
ByteBuffer bb = null;
int len = (int) (end - start + 1);
int hedgedReadId = 0;
block = getBlockAt(block.getStartOffset(), false);
block = getBlockAt(block.getStartOffset());
while (true) {
// see HDFS-6591, this metric is used to verify/catch unnecessary loops
hedgedReadOpsLoopNumForTesting++;