/** Move a persisted replica from lazypersist directory to a subdirectory under finalized. */
File activateSavedReplica(Block b, File metaFile, File blockFile) throws IOException {
final File blockDir = DatanodeUtil.idToBlockDir(finalizedDir, b.getBlockId());
final File targetBlockFile = new File(blockDir, blockFile.getName());
final File targetMetaFile = new File(blockDir, metaFile.getName());
FileUtils.moveFile(blockFile, targetBlockFile);
FsDatasetImpl.LOG.info("Moved " + blockFile + " to " + targetBlockFile);
FileUtils.moveFile(metaFile, targetMetaFile);
FsDatasetImpl.LOG.info("Moved " + metaFile + " to " + targetMetaFile);
return targetBlockFile;
}
/**
* Read in the cached DU value and return it if it is less than 600 seconds old (DU update
* interval). Slight imprecision of dfsUsed is not critical and skipping DU can significantly
* shorten the startup time. If the cached value is not available or too old, -1 is returned.
*/
long loadDfsUsed() {
long cachedDfsUsed;
long mtime;
Scanner sc;
try {
sc = new Scanner(new File(currentDir, DU_CACHE_FILE), "UTF-8");
} catch (FileNotFoundException fnfe) {
return -1;
}
try {
// Get the recorded dfsUsed from the file.
if (sc.hasNextLong()) {
cachedDfsUsed = sc.nextLong();
} else {
return -1;
}
// Get the recorded mtime from the file.
if (sc.hasNextLong()) {
mtime = sc.nextLong();
} else {
return -1;
}
// Return the cached value if mtime is okay.
if (mtime > 0 && (Time.now() - mtime < 600000L)) {
FsDatasetImpl.LOG.info("Cached dfsUsed found for " + currentDir + ": " + cachedDfsUsed);
return cachedDfsUsed;
}
return -1;
} finally {
sc.close();
}
}
void getVolumeMap(ReplicaMap volumeMap, final RamDiskReplicaTracker lazyWriteReplicaMap)
throws IOException {
// Recover lazy persist replicas, they will be added to the volumeMap
// when we scan the finalized directory.
if (lazypersistDir.exists()) {
int numRecovered = moveLazyPersistReplicasToFinalized(lazypersistDir);
FsDatasetImpl.LOG.info("Recovered " + numRecovered + " replicas from " + lazypersistDir);
}
// add finalized replicas
addToReplicasMap(volumeMap, finalizedDir, lazyWriteReplicaMap, true);
// add rbw replicas
addToReplicasMap(volumeMap, rbwDir, lazyWriteReplicaMap, false);
}
