public static String store2Hdfs(Key srcKey) {
assert srcKey._kb[0] != Key.ARRAYLET_CHUNK;
assert PersistHdfs.getPathForKey(srcKey) != null; // Validate key name
Value v = DKV.get(srcKey);
if (v == null) return "Key " + srcKey + " not found";
if (v._isArray == 0) { // Simple chunk?
v.setHdfs(); // Set to HDFS and be done
return null; // Success
}
// For ValueArrays, make the .hex header
ValueArray ary = ValueArray.value(v);
String err = PersistHdfs.freeze(srcKey, ary);
if (err != null) return err;
// The task managing which chunks to write next,
// store in a known key
TaskStore2HDFS ts = new TaskStore2HDFS(srcKey);
Key selfKey = ts.selfKey();
UKV.put(selfKey, ts);
// Then start writing chunks in-order with the zero chunk
H2ONode chk0_home = ValueArray.getChunkKey(0, srcKey).home_node();
RPC.call(ts.chunkHome(), ts);
// Watch the progress key until it gets removed or an error appears
long idx = 0;
while (UKV.get(selfKey, ts) != null) {
if (ts._indexFrom != idx) {
System.out.print(" " + idx + "/" + ary.chunks());
idx = ts._indexFrom;
}
if (ts._err != null) { // Found an error?
UKV.remove(selfKey); // Cleanup & report
return ts._err;
}
try {
Thread.sleep(100);
} catch (InterruptedException e) {
}
}
System.out.println(" " + ary.chunks() + "/" + ary.chunks());
// PersistHdfs.refreshHDFSKeys();
return null;
}
@Override
public void compute() {
String path = null; // getPathFromValue(val);
ValueArray ary = ValueArray.value(_arykey);
Key self = selfKey();
while (_indexFrom < ary.chunks()) {
Key ckey = ary.getChunkKey(_indexFrom++);
if (!ckey.home()) { // Next chunk not At Home?
RPC.call(chunkHome(), this); // Hand the baton off to the next node/chunk
return;
}
Value val = DKV.get(ckey); // It IS home, so get the data
_err = PersistHdfs.appendChunk(_arykey, val);
if (_err != null) return;
UKV.put(self, this); // Update the progress/self key
}
// We did the last chunk. Removing the selfKey is the signal to the web
// thread that All Done.
UKV.remove(self);
}