/** How many copies of this block is pending replication? */
int getNumReplicas(Block block) {
synchronized (pendingReplications) {
PendingBlockInfo found = pendingReplications.get(block);
if (found != null) {
return found.getNumReplicas();
}
}
return 0;
}
/** Add a block to the list of pending Replications */
void add(Block block, int numReplicas) {
synchronized (pendingReplications) {
PendingBlockInfo found = pendingReplications.get(block);
if (found == null) {
pendingReplications.put(block, new PendingBlockInfo(numReplicas));
} else {
found.incrementReplicas(numReplicas);
found.setTimeStamp();
}
}
}
/**
* One replication request for this block has finished. Decrement the number of pending
* replication requests for this block.
*/
void remove(Block block) {
synchronized (pendingReplications) {
PendingBlockInfo found = pendingReplications.get(block);
if (found != null) {
FSNamesystem.LOG.debug("Removing pending replication for block" + block);
found.decrementReplicas();
if (found.getNumReplicas() <= 0) {
pendingReplications.remove(block);
}
}
}
}
/** Iterate through all items and detect timed-out items */
void pendingReplicationCheck() {
synchronized (pendingReplications) {
Iterator iter = pendingReplications.entrySet().iterator();
long now = FSNamesystem.now();
FSNamesystem.LOG.debug("PendingReplicationMonitor checking Q");
while (iter.hasNext()) {
Map.Entry entry = (Map.Entry) iter.next();
PendingBlockInfo pendingBlock = (PendingBlockInfo) entry.getValue();
if (now > pendingBlock.getTimeStamp() + timeout) {
Block block = (Block) entry.getKey();
synchronized (timedOutItems) {
timedOutItems.add(block);
}
FSNamesystem.LOG.warn("PendingReplicationMonitor timed out block " + block);
iter.remove();
}
}
}
}