/*
* 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.flume.tools;
import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.util.List;
import java.util.Locale;
import java.util.concurrent.atomic.AtomicInteger;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
public class DirectMemoryUtils {
private static final Logger LOG = LoggerFactory
.getLogger(DirectMemoryUtils.class);
private static final String MAX_DIRECT_MEMORY_PARAM =
"-XX:MaxDirectMemorySize=";
private static final long DEFAULT_SIZE = getDefaultDirectMemorySize();
private static final AtomicInteger allocated = new AtomicInteger(0);
public static ByteBuffer allocate(int size) {
Preconditions.checkArgument(size > 0, "Size must be greater than zero");
long maxDirectMemory = getDirectMemorySize();
long allocatedCurrently = allocated.get();
LOG.info("Direct Memory Allocation: " +
" Allocation = " + size +
", Allocated = " + allocatedCurrently +
", MaxDirectMemorySize = " + maxDirectMemory +
", Remaining = " + Math.max(0,(maxDirectMemory - allocatedCurrently)));
try {
ByteBuffer result = ByteBuffer.allocateDirect(size);
allocated.addAndGet(size);
return result;
} catch(OutOfMemoryError error) {
LOG.error("Error allocating " + size + ", you likely want" +
" to increase " + MAX_DIRECT_MEMORY_PARAM, error);
throw error;
}
}
public static void clean(ByteBuffer buffer) throws Exception {
Preconditions.checkArgument(buffer.isDirect(),
"buffer isn't direct!");
Method cleanerMethod = buffer.getClass().getMethod("cleaner");
cleanerMethod.setAccessible(true);
Object cleaner = cleanerMethod.invoke(buffer);
Method cleanMethod = cleaner.getClass().getMethod("clean");
cleanMethod.setAccessible(true);
cleanMethod.invoke(cleaner);
allocated.getAndAdd(-buffer.capacity());
long maxDirectMemory = getDirectMemorySize();
LOG.info("Direct Memory Deallocation: " +
", Allocated = " + allocated.get() +
", MaxDirectMemorySize = " + maxDirectMemory +
", Remaining = " + Math.max(0, (maxDirectMemory - allocated.get())));
}
public static long getDirectMemorySize() {
RuntimeMXBean RuntimemxBean = ManagementFactory.getRuntimeMXBean();
List<String> arguments = Lists.reverse(RuntimemxBean.getInputArguments());
long multiplier = 1; //for the byte case.
for (String s : arguments) {
if (s.contains(MAX_DIRECT_MEMORY_PARAM)) {
String memSize = s.toLowerCase(Locale.ENGLISH)
.replace(MAX_DIRECT_MEMORY_PARAM.toLowerCase(Locale.ENGLISH), "").trim();
if (memSize.contains("k")) {
multiplier = 1024;
}
else if (memSize.contains("m")) {
multiplier = 1048576;
}
else if (memSize.contains("g")) {
multiplier = 1073741824;
}
memSize = memSize.replaceAll("[^\\d]", "");
long retValue = Long.parseLong(memSize);
return retValue * multiplier;
}
}
return DEFAULT_SIZE;
}
private static long getDefaultDirectMemorySize() {
try {
Class<?> VM = Class.forName("sun.misc.VM");
Method maxDirectMemory = VM.getDeclaredMethod("maxDirectMemory", (Class<?>)null);
Object result = maxDirectMemory.invoke(null, (Object[])null);
if(result != null && result instanceof Long) {
return (Long)result;
}
} catch (Exception e) {
LOG.info("Unable to get maxDirectMemory from VM: " +
e.getClass().getSimpleName() + ": " + e.getMessage());
}
// default according to VM.maxDirectMemory()
return Runtime.getRuntime().maxMemory();
}
}