org.apache.hadoop.hive.ql.exec.tez.LlapObjectCache Maven / Gradle / Ivy
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* 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.exec.tez;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.locks.ReentrantLock;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
/**
* LlapObjectCache. Llap implementation for the shared object cache.
*
*/
public class LlapObjectCache implements org.apache.hadoop.hive.ql.exec.ObjectCache {
private static final Logger LOG = LoggerFactory.getLogger(LlapObjectCache.class.getName());
private static ExecutorService staticPool = Executors.newCachedThreadPool();
private final Cache registry = CacheBuilder.newBuilder().softValues().build();
private final Map locks = new HashMap();
private final ReentrantLock lock = new ReentrantLock();
@Override
public void release(String key) {
// nothing to do, soft references will clean themselves up
}
@SuppressWarnings("unchecked")
@Override
public T retrieve(String key) throws HiveException {
T value = null;
lock.lock();
try {
value = (T) registry.getIfPresent(key);
if (value != null && LOG.isDebugEnabled()) {
LOG.debug("Found " + key + " in cache");
}
return value;
} finally {
lock.unlock();
}
}
@SuppressWarnings("unchecked")
@Override
public T retrieve(String key, Callable fn) throws HiveException {
T value = null;
ReentrantLock objectLock = null;
lock.lock();
try {
value = (T) registry.getIfPresent(key);
if (value != null) {
if (LOG.isDebugEnabled()) {
LOG.debug("Found " + key + " in cache");
}
return value;
}
if (locks.containsKey(key)) {
objectLock = locks.get(key);
} else {
objectLock = new ReentrantLock();
locks.put(key, objectLock);
}
} finally {
lock.unlock();
}
objectLock.lock();
try{
lock.lock();
try {
value = (T) registry.getIfPresent(key);
if (value != null) {
if (LOG.isDebugEnabled()) {
LOG.debug("Found " + key + " in cache");
}
return value;
}
} finally {
lock.unlock();
}
try {
value = fn.call();
} catch (Exception e) {
throw new HiveException(e);
}
lock.lock();
try {
if (LOG.isDebugEnabled()) {
LOG.debug("Caching new object for key: " + key);
}
registry.put(key, value);
locks.remove(key);
} finally {
lock.unlock();
}
} finally {
objectLock.unlock();
}
return value;
}
@Override
public Future retrieveAsync(final String key, final Callable fn) throws HiveException {
return staticPool.submit(new Callable() {
@Override
public T call() throws Exception {
return retrieve(key, fn);
}
});
}
@Override
public void remove(String key) {
if (LOG.isDebugEnabled()) {
LOG.debug("Removing key: " + key);
}
registry.invalidate(key);
}
}