org.apache.activemq.usage.MemoryUsage Maven / Gradle / Ivy
/**
* 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.activemq.usage;
import java.util.concurrent.TimeUnit;
/**
* Used to keep track of how much of something is being used so that a
* productive working set usage can be controlled. Main use case is manage
* memory usage.
*
* @org.apache.xbean.XBean
*
*/
public class MemoryUsage extends Usage {
private long usage;
public MemoryUsage() {
this(null, null);
}
/**
* Create the memory manager linked to a parent. When the memory manager is
* linked to a parent then when usage increased or decreased, the parent's
* usage is also increased or decreased.
*
* @param parent
*/
public MemoryUsage(MemoryUsage parent) {
this(parent, "default");
}
public MemoryUsage(String name) {
this(null, name);
}
public MemoryUsage(MemoryUsage parent, String name) {
this(parent, name, 1.0f);
}
public MemoryUsage(MemoryUsage parent, String name, float portion) {
super(parent, name, portion);
}
/**
* @throws InterruptedException
*/
@Override
public void waitForSpace() throws InterruptedException {
if (parent != null) {
parent.waitForSpace();
}
usageLock.readLock().lock();
try {
if (percentUsage >= 100 && isStarted()) {
usageLock.readLock().unlock();
usageLock.writeLock().lock();
try {
while (percentUsage >= 100 && isStarted()) {
waitForSpaceCondition.await();
}
} finally {
usageLock.writeLock().unlock();
usageLock.readLock().lock();
}
}
if (percentUsage >= 100 && !isStarted()) {
throw new InterruptedException("waitForSpace stopped during wait.");
}
} finally {
usageLock.readLock().unlock();
}
}
/**
* @param timeout
* @throws InterruptedException
* @return true if space
*/
@Override
public boolean waitForSpace(long timeout) throws InterruptedException {
if (parent != null) {
if (!parent.waitForSpace(timeout)) {
return false;
}
}
usageLock.readLock().lock();
try {
if (percentUsage >= 100) {
usageLock.readLock().unlock();
usageLock.writeLock().lock();
try {
while (percentUsage >= 100 ) {
waitForSpaceCondition.await(timeout, TimeUnit.MILLISECONDS);
}
usageLock.readLock().lock();
} finally {
usageLock.writeLock().unlock();
}
}
return percentUsage < 100;
} finally {
usageLock.readLock().unlock();
}
}
@Override
public boolean isFull() {
if (parent != null && parent.isFull()) {
return true;
}
usageLock.readLock().lock();
try {
return percentUsage >= 100;
} finally {
usageLock.readLock().unlock();
}
}
/**
* Tries to increase the usage by value amount but blocks if this object is
* currently full.
*
* @param value
* @throws InterruptedException
*/
public void enqueueUsage(long value) throws InterruptedException {
waitForSpace();
increaseUsage(value);
}
/**
* Increases the usage by the value amount.
*
* @param value
*/
public void increaseUsage(long value) {
if (value == 0) {
return;
}
usageLock.writeLock().lock();
try {
usage += value;
setPercentUsage(caclPercentUsage());
} finally {
usageLock.writeLock().unlock();
}
if (parent != null) {
parent.increaseUsage(value);
}
}
/**
* Decreases the usage by the value amount.
*
* @param value
*/
public void decreaseUsage(long value) {
if (value == 0) {
return;
}
usageLock.writeLock().lock();
try {
usage -= value;
setPercentUsage(caclPercentUsage());
} finally {
usageLock.writeLock().unlock();
}
if (parent != null) {
parent.decreaseUsage(value);
}
}
@Override
protected long retrieveUsage() {
return usage;
}
@Override
public long getUsage() {
return usage;
}
public void setUsage(long usage) {
this.usage = usage;
}
public void setPercentOfJvmHeap(int percentOfJvmHeap) {
if (percentOfJvmHeap > 0) {
setLimit(Math.round(Runtime.getRuntime().maxMemory() * percentOfJvmHeap / 100.0));
}
}
}