synchronized List<Block> invalidateWork(final DatanodeDescriptor dn) {
final long delay = getInvalidationDelay();
if (delay > 0) {
if (BlockManager.LOG.isDebugEnabled()) {
BlockManager.LOG.debug(
"Block deletion is delayed during NameNode startup. "
+ "The deletion will start after "
+ delay
+ " ms.");
}
return null;
}
final LightWeightHashSet<Block> set = node2blocks.get(dn);
if (set == null) {
return null;
}
// # blocks that can be sent in one message is limited
final int limit = blockInvalidateLimit;
final List<Block> toInvalidate = set.pollN(limit);
// If we send everything in this message, remove this node entry
if (set.isEmpty()) {
remove(dn);
}
dn.addBlocksToBeInvalidated(toInvalidate);
numBlocks -= toInvalidate.size();
return toInvalidate;
}
/** Remove the block from the specified storage. */
synchronized void remove(final DatanodeInfo dn, final Block block) {
final LightWeightHashSet<Block> v = node2blocks.get(dn);
if (v != null && v.remove(block)) {
numBlocks--;
if (v.isEmpty()) {
node2blocks.remove(dn);
}
}
}