/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hive.ql.lockmgr;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.Driver.LockedDriverState;
import org.apache.hadoop.hive.ql.lockmgr.HiveLockObject.HiveLockObjectData;
import org.apache.hadoop.hive.ql.metadata.*;
import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.ReentrantLock;
/**
* shared lock manager for dedicated hive server. all locks are managed in memory
*/
public class EmbeddedLockManager implements HiveLockManager {
private static final Logger LOG = LoggerFactory.getLogger("EmbeddedHiveLockManager");
private final Node root = new Node();
private HiveLockManagerCtx ctx;
private long sleepTime = 1000;
private int numRetriesForLock = 0;
private int numRetriesForUnLock = 0;
public EmbeddedLockManager() {
}
@Override
public void setContext(HiveLockManagerCtx ctx) throws LockException {
this.ctx = ctx;
refresh();
}
@Override
public HiveLock lock(HiveLockObject key, HiveLockMode mode, boolean keepAlive)
throws LockException {
return lock(key, mode, numRetriesForLock, sleepTime);
}
@Override
public List<HiveLock> lock(List<HiveLockObj> objs, boolean keepAlive, LockedDriverState lDrvState) throws LockException {
return lock(objs, numRetriesForLock, sleepTime);
}
@Override
public void unlock(HiveLock hiveLock) throws LockException {
unlock(hiveLock, numRetriesForUnLock, sleepTime);
}
@Override
public void releaseLocks(List<HiveLock> hiveLocks) {
releaseLocks(hiveLocks, numRetriesForUnLock, sleepTime);
}
@Override
public List<HiveLock> getLocks(boolean verifyTablePartitions, boolean fetchData)
throws LockException {
return getLocks(verifyTablePartitions, fetchData, ctx.getConf());
}
@Override
public List<HiveLock> getLocks(HiveLockObject key, boolean verifyTablePartitions,
boolean fetchData) throws LockException {
return getLocks(key, verifyTablePartitions, fetchData, ctx.getConf());
}
@Override
public void prepareRetry() {
}
@Override
public void refresh() {
HiveConf conf = ctx.getConf();
sleepTime = conf.getTimeVar(
HiveConf.ConfVars.HIVE_LOCK_SLEEP_BETWEEN_RETRIES, TimeUnit.MILLISECONDS);
numRetriesForLock = conf.getIntVar(HiveConf.ConfVars.HIVE_LOCK_NUMRETRIES);
numRetriesForUnLock = conf.getIntVar(HiveConf.ConfVars.HIVE_UNLOCK_NUMRETRIES);
}
public HiveLock lock(HiveLockObject key, HiveLockMode mode, int numRetriesForLock, long sleepTime)
throws LockException {
for (int i = 0; i <= numRetriesForLock; i++) {
if (i > 0) {
sleep(sleepTime);
}
HiveLock lock = lockPrimitive(key, mode);
if (lock != null) {
return lock;
}
}
return null;
}
private void sleep(long sleepTime) {
try {
Thread.sleep(sleepTime);
} catch (InterruptedException e) {
// ignore
}
}
public List<HiveLock> lock(List<HiveLockObj> objs, int numRetriesForLock, long sleepTime)
throws LockException {
sortLocks(objs);
for (int i = 0; i <= numRetriesForLock; i++) {
if (i > 0) {
sleep(sleepTime);
}
List<HiveLock> locks = lockPrimitive(objs, numRetriesForLock, sleepTime);
if (locks != null) {
return locks;
}
}
return null;
}
private HiveLock lockPrimitive(HiveLockObject key, HiveLockMode mode) throws LockException {
if (root.lock(key.getPaths(), key.getData(), mode == HiveLockMode.EXCLUSIVE)) {
return new SimpleHiveLock(key, mode);
}
return null;
}
private List<HiveLock> lockPrimitive(List<HiveLockObj> objs, int numRetriesForLock,
long sleepTime) throws LockException {
List<HiveLock> locks = new ArrayList<HiveLock>();
for (HiveLockObj obj : objs) {
HiveLock lock = lockPrimitive(obj.getObj(), obj.getMode());
if (lock == null) {
releaseLocks(locks, numRetriesForLock, sleepTime);
return null;
}
locks.add(lock);
}
return locks;
}
private void sortLocks(List<HiveLockObj> objs) {
Collections.sort(objs, new Comparator<HiveLockObj>() {
@Override
public int compare(HiveLockObj o1, HiveLockObj o2) {
int cmp = o1.getName().compareTo(o2.getName());
if (cmp == 0) {
if (o1.getMode() == o2.getMode()) {
return cmp;
}
// EXCLUSIVE locks occur before SHARED locks
if (o1.getMode() == HiveLockMode.EXCLUSIVE) {
return -1;
}
return +1;
}
return cmp;
}
});
}
public void unlock(HiveLock hiveLock, int numRetriesForUnLock, long sleepTime)
throws LockException {
String[] paths = hiveLock.getHiveLockObject().getPaths();
HiveLockObjectData data = hiveLock.getHiveLockObject().getData();
for (int i = 0; i <= numRetriesForUnLock; i++) {
if (i > 0) {
sleep(sleepTime);
}
if (root.unlock(paths, data)) {
return;
}
}
throw new LockException("Failed to release lock " + hiveLock);
}
public void releaseLocks(List<HiveLock> hiveLocks, int numRetriesForUnLock, long sleepTime) {
for (HiveLock locked : hiveLocks) {
try {
unlock(locked, numRetriesForUnLock, sleepTime);
} catch (LockException e) {
LOG.info("Failed to unlock ", e);
}
}
}
public List<HiveLock> getLocks(boolean verifyTablePartitions, boolean fetchData, HiveConf conf)
throws LockException {
return root.getLocks(verifyTablePartitions, fetchData, conf);
}
public List<HiveLock> getLocks(HiveLockObject key, boolean verifyTablePartitions,
boolean fetchData, HiveConf conf) throws LockException {
return root.getLocks(key.getPaths(), verifyTablePartitions, fetchData, conf);
}
// from ZooKeeperHiveLockManager
private HiveLockObject verify(boolean verify, String[] names, HiveLockObjectData data,
HiveConf conf) throws LockException {
if (!verify) {
return new HiveLockObject(names, data);
}
String database = names[0];
String table = names[1];
try {
Hive db = Hive.get(conf);
Table tab = db.getTable(database, table, false);
if (tab == null) {
return null;
}
if (names.length == 2) {
return new HiveLockObject(tab, data);
}
Map<String, String> partSpec = new HashMap<String, String>();
for (int indx = 2; indx < names.length; indx++) {
String[] partVals = names[indx].split("=");
partSpec.put(partVals[0], partVals[1]);
}
Partition partn;
try {
partn = db.getPartition(tab, partSpec, false);
} catch (HiveException e) {
partn = null;
}
if (partn == null) {
return new HiveLockObject(new DummyPartition(tab, null, partSpec), data);
}
return new HiveLockObject(partn, data);
} catch (Exception e) {
throw new LockException(e);
}
}
@Override
public void close() {
root.lock.lock();
try {
root.datas = null;
root.children = null;
} finally {
root.lock.unlock();
}
}
private class Node {
private boolean exclusive;
private Map<String, Node> children;
private Map<String, HiveLockObjectData> datas;
private final ReentrantLock lock = new ReentrantLock();
public Node() {
}
public void set(HiveLockObjectData data, boolean exclusive) {
this.exclusive = exclusive;
if (datas == null) {
datas = new HashMap<String, HiveLockObjectData>(3);
}
datas.put(data.getQueryId(), data);
}
public boolean lock(String[] paths, HiveLockObjectData data, boolean exclusive) {
return lock(paths, 0, data, exclusive);
}
public boolean unlock(String[] paths, HiveLockObjectData data) {
return unlock(paths, 0, data);
}
private List<HiveLock> getLocks(boolean verify, boolean fetchData, HiveConf conf)
throws LockException {
if (!root.hasChild()) {
return Collections.emptyList();
}
List<HiveLock> locks = new ArrayList<HiveLock>();
getLocks(new Stack<String>(), verify, fetchData, locks, conf);
return locks;
}
private List<HiveLock> getLocks(String[] paths, boolean verify, boolean fetchData,
HiveConf conf) throws LockException {
if (!root.hasChild()) {
return Collections.emptyList();
}
List<HiveLock> locks = new ArrayList<HiveLock>();
getLocks(paths, 0, verify, fetchData, locks, conf);
return locks;
}
private boolean lock(String[] paths, int index, HiveLockObjectData data, boolean exclusive) {
if (!lock.tryLock()) {
return false;
}
try {
if (index == paths.length) {
if (this.exclusive || exclusive && hasLock()) {
return false;
}
set(data, exclusive);
return true;
}
Node child;
if (children == null) {
children = new HashMap<String, Node>(3);
children.put(paths[index], child = new Node());
} else {
child = children.get(paths[index]);
if (child == null) {
children.put(paths[index], child = new Node());
}
}
return child.lock(paths, index + 1, data, exclusive);
} finally {
lock.unlock();
}
}
private boolean unlock(String[] paths, int index, HiveLockObjectData data) {
if (!lock.tryLock()) {
return false;
}
try {
if (index == paths.length) {
if (hasLock()) {
datas.remove(data.getQueryId());
}
return true;
}
Node child = children == null ? null : children.get(paths[index]);
if (child == null) {
return true; // should not happen
}
if (child.unlock(paths, index + 1, data)) {
if (!child.hasLock() && !child.hasChild()) {
children.remove(paths[index]);
}
return true;
}
return false;
} finally {
lock.unlock();
}
}
private void getLocks(Stack<String> names, boolean verify,
boolean fetchData, List<HiveLock> locks, HiveConf conf) throws LockException {
lock.lock();
try {
if (hasLock()) {
getLocks(names.toArray(new String[names.size()]), verify, fetchData, locks, conf);
}
if (children != null) {
for (Map.Entry<String, Node> entry : children.entrySet()) {
names.push(entry.getKey());
entry.getValue().getLocks(names, verify, fetchData, locks, conf);
names.pop();
}
}
} finally {
lock.unlock();
}
}
private void getLocks(String[] paths, int index, boolean verify,
boolean fetchData, List<HiveLock> locks, HiveConf conf) throws LockException {
lock.lock();
try {
if (index == paths.length) {
getLocks(paths, verify, fetchData, locks, conf);
return;
}
Node child = children.get(paths[index]);
if (child != null) {
child.getLocks(paths, index + 1, verify, fetchData, locks, conf);
}
} finally {
lock.unlock();
}
}
private void getLocks(String[] paths, boolean verify, boolean fetchData, List<HiveLock> locks,
HiveConf conf) throws LockException {
HiveLockMode lockMode = getLockMode();
if (fetchData) {
for (HiveLockObjectData data : datas.values()) {
HiveLockObject lock = verify(verify, paths, data, conf);
if (lock != null) {
locks.add(new SimpleHiveLock(lock, lockMode));
}
}
} else {
HiveLockObject lock = verify(verify, paths, null, conf);
if (lock != null) {
locks.add(new SimpleHiveLock(lock, lockMode));
}
}
}
private HiveLockMode getLockMode() {
return exclusive ? HiveLockMode.EXCLUSIVE : HiveLockMode.SHARED;
}
private boolean hasLock() {
return datas != null && !datas.isEmpty();
}
private boolean hasChild() {
return children != null && !children.isEmpty();
}
}
private static class SimpleHiveLock extends HiveLock {
private final HiveLockObject lockObj;
private final HiveLockMode lockMode;
public SimpleHiveLock(HiveLockObject lockObj, HiveLockMode lockMode) {
this.lockObj = lockObj;
this.lockMode = lockMode;
}
@Override
public HiveLockObject getHiveLockObject() {
return lockObj;
}
@Override
public HiveLockMode getHiveLockMode() {
return lockMode;
}
@Override
public String toString() {
return lockMode + "=" + lockObj.getDisplayName() + "(" + lockObj.getData() + ")";
}
@Override
public boolean equals(Object o) {
if (!(o instanceof SimpleHiveLock)) {
return false;
}
SimpleHiveLock simpleLock = (SimpleHiveLock) o;
return lockObj.equals(simpleLock.getHiveLockObject()) &&
lockMode == simpleLock.getHiveLockMode();
}
}
}