if (!blockInfo.getBlockUCState().equals(BlockUCState.COMPLETE)) {
// We don't try to cache blocks that are under construction.
continue;
}
Block block = new Block(blockInfo.getBlockId());
CachedBlock ncblock = new CachedBlock(block.getBlockId(),
directive.getReplication(), mark);
CachedBlock ocblock = cachedBlocks.get(ncblock);
if (ocblock == null) {
cachedBlocks.put(ncblock);
} else {
// Update bytesUsed using the current replication levels.
// Assumptions: we assume that all the blocks are the same length
// on each datanode. We can assume this because we're only caching
// blocks in state COMMITTED.
// Note that if two directives are caching the same block(s), they will
// both get them added to their bytesCached.
List<DatanodeDescriptor> cachedOn =
ocblock.getDatanodes(Type.CACHED);
long cachedByBlock = Math.min(cachedOn.size(),
directive.getReplication()) * blockInfo.getNumBytes();
cachedTotal += cachedByBlock;
if ((mark != ocblock.getMark()) ||
(ocblock.getReplication() < directive.getReplication())) {
//
// Overwrite the block's replication and mark in two cases:
//
// 1. If the mark on the CachedBlock is different from the mark for
// this scan, that means the block hasn't been updated during this
// scan, and we should overwrite whatever is there, since it is no
// longer valid.
//
// 2. If the replication in the CachedBlock is less than what the
// directive asks for, we want to increase the block's replication
// field to what the directive asks for.
//
ocblock.setReplicationAndMark(directive.getReplication(), mark);
}
}
}
// Increment the "cached" statistics
directive.addBytesCached(cachedTotal);