내용 목차
JEUS MBean 정보를 모니터링하는 4가지 중요한 예제를 설명한다.
설명하는 모든 예제에서 MBean 서버 정보를 조회할 때 RemoteMBeanServerFactory를 이용한다. MBean 서버를 얻어오는 다른 방법에 대한 자세한 내용은 “제3장 JMX 애플리케이션 개발”을 참고한다.
Servlet Thread Info 모니터링 예제는 웹 컨테이너의 리스너의 정보, 특히 Thread Pool과 각 Thread에 대한 정보를 모니터링한다.
이 예제를 통해 모니터링하는 정보는 다음과 같다.
현재 할당된 Worker Thread의 수(current thread count)
Thread Pool을 유지하는 최대 Thread의 개수(max thread count)
Wait-Queue에 적체된 클라이언트의 수(wait queue count)
다음은 Servlet Thread Info 모니터링 예제이다.
package monitoring;
import java.util.*;
import javax.management.MBeanServerConnection;
import javax.management.ObjectName;
import javax.management.ObjectInstance;
import javax.management.MalformedObjectNameException;
import javax.management.MBeanServerInvocationHandler;
import jeus.management.j2ee.servlet.*;
public class ServletThreadInfo {
public void showInfo(MBeanServerConnection mBeanServer, String targetName)
throws Exception {
System.out.println("=== Servlet Thread Info ===");
// Get the object name of the servlet engine using JMX Standard API
// Otherwise, the object name could be queried through MBeanServer.
// Please see JEUS MBean API javadoc for more concrete name, key properties.
ObjectName name = new ObjectName("JEUS:jeusType=WebEngine,J2EEServer=" +
targetName + ",*");
Set names = mBeanServer.queryMBeans(name, null);
if (names == null || names.size() == 0) {
System.out.println("there is no servlet engine");
return;
}
// Choose one servlet engine from the returned object names
Iterator it = names.iterator();
ObjectName fullName = null;
while (it.hasNext()) {
fullName = ((ObjectInstance)it.next()).getObjectName();
break;
}
assert fullName != null;
WebEngineMoMBean engineMBean =
(WebEngineMoMBean)MBeanServerInvocationHandler.newProxyInstance(mBeanServer,
fullName, WebEngineMoMBean.class, false);
// Get listeners from WebEngine
String[] listeners = engineMBean.getWebListeners();
if(listeners == null || listeners.length == 0){
return;
}
String webEngineName = engineMBean.getObjectName().getKeyProperty("name");
for(int i = 0; i < listeners.length; i++) {
ObjectName listener = new ObjectName(listeners[i]);
WebListenerMoMBean listenerMBean=
(WebListenerMoMBean) MBeanServerInvocationHandler.newProxyInstance
(mBeanServer, listener, WebListenerMoMBean.class, false);
String[] tpoolNames = listenerMBean.getThreadPools();
// Get stats from thread pools
if (tpoolNames != null) {
showThreadPoolStats(mBeanServer, webEngineName, tpoolNames);
}
}
System.out.println();
}
private void showThreadPoolStats(MBeanServerConnection mBeanServer,
String contextGroupName,
String[] tpoolNames)
throws MalformedObjectNameException {
for (int k = 0; k < tpoolNames.length; k++) {
ObjectName tpool = new ObjectName(tpoolNames[k]);
System.out.println("[MBean] " + tpool);
ThreadPoolMoMBean tpoolMBean =
(ThreadPoolMoMBean)MBeanServerInvocationHandler.newProxyInstance(
mBeanServer,tpool, ThreadPoolMoMBean.class, false);
ThreadPoolStatsImpl stats = (ThreadPoolStatsImpl) tpoolMBean.getstats();
System.out.println("Listener: " + contextGroupName
+ "/" + tpool.getKeyProperty("name"));
System.out.println("- current thread count : "
+ stats.getAllThreadCount().getCount());
System.out.println("- max thread count : "
+ stats.getMaxThreadCount().getCount());
if (stats.getStatisticVersion() == ThreadPoolStatsImpl.NIO_VERSION) {
// pipeline
System.out.println("- total connection count : "
+ stats.getTotalConnectionCount().getCount());
System.out.println("- max queue count : "
+ stats.getMaxQueueCount().getCount());
System.out.println("- current queue count : "
+ stats.getCurrentQueueCount().getCount());
System.out.println("- remain queue count : "
+ stats.getRemainQueueCount().getCount());
System.out.println("- peak queue count : "
+ stats.getPeakQueueCount().getCount());
System.out.println("- total queue count : "
+ stats.getTotalQueueCount().getCount());
System.out.println("- difference queue 1m count : "
+ stats.getDifferenceQueue1MCount().getCount());
System.out.println("- difference queue 5m count : "
+ stats.getDifferenceQueue5MCount().getCount());
System.out.println("- difference queue 15m count : "
+ stats.getDifferenceQueue15MCount().getCount());
System.out.println("- overflow queue count : "
+ stats.getOverflowCount().getCount());
System.out.println("- average queue time : "
+ stats.getQueueWaitTimeAverage().getCount() + "(ms)");
} else {
System.out.println("- wait queue count : "
+ stats.getWaitQueueCount().getCount());
}
System.out.println();
}
}
}
Thread Pool Info 모니터링 예제는 JEUS 에서 사용하는 여러 Thread Pool의 상태를 모니터링한다.
이 예제를 통해 모니터링하는 정보는 다음과 같다.
Thread Pool 크기(size)에 대한 정보
Thread Pool 통계(stats) 정보
Thread 들의 수행시간에 대한 통계(execution time stats) 정보
Waiting-Queue 크기에 대한 통계(size stats) 정보
다음은 Thread Info 모니터링 예제이다.
package monitoring;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Set;
import javax.management.MBeanServerConnection;
import javax.management.MBeanServerInvocationHandler;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.j2ee.statistics.TimeStatistic;
import javax.management.j2ee.statistics.RangeStatistic;
import javax.naming.*;
import jeus.jndi.JNSConstants;
import jeus.management.JMXConstants;
import jeus.management.RemoteMBeanServerFactory;
import jeus.management.j2ee.thread.ThreadPoolMBean;
import jeus.management.j2ee.thread.stats.ThreadPoolStats;
public class ThreadPoolInfo {
public void showInfo(MBeanServerConnection mBeanServer, String name)
throws Exception {
System.out.println("=== ThreadPool Info ===");
// Get the object names of the thread pools.
// Please see JEUS MBean API javadoc for more concrete name, key
// properties.
ObjectName objectNames = new ObjectName("JEUS:jeusType=ThreadPool,*");
Set tpMBeans = mBeanServer.queryMBeans(objectNames, null);
for (Iterator i = tpMBeans.iterator(); i.hasNext();) {
ObjectName mbeanName = ((ObjectInstance) i.next()).getObjectName();
// thread pool name
System.out.println("[Thread-pool : "
+ mbeanName.getKeyProperty("name") + "]");
System.out.println("[MBean] " + mbeanName);
ThreadPoolMBean pool =
(ThreadPoolMBean)MBeanServerInvocationHandler.newProxyInstance(
mBeanServer, mbeanName, ThreadPoolMBean.class, false);
// ThreadPool Size
System.out.println("-size : " + pool.getPoolSize());
System.out.println("-core size : " + pool.getCorePoolSize());
System.out.println("-largest Size : " + pool.getLargestPoolSize());
System.out.println("-max size : " + pool.getMaximumPoolSize());
System.out.println("-queue size : " + pool.getWorkQueueSize());
// ThreadPool Stats
ThreadPoolStats stats = (ThreadPoolStats) pool.getstats();
TimeStatistic executionTimeStats = stats.getThreadExecutionTime();
TimeStatistic waitingTimeStats = stats.getQueueWaitingTime();
System.out.println("# Thread Execution Time Stats");
System.out.println("--unit : " + executionTimeStats.getUnit());
System.out.println("--count : " + executionTimeStats.getCount());
System.out.println("--min time : " + executionTimeStats.getMinTime());
System.out.println("--max time : " + executionTimeStats.getMaxTime());
System.out.println("# Queue Waiting Time Stats");
System.out.println("--unit : " + waitingTimeStats.getUnit());
System.out.println("--count : " + waitingTimeStats.getCount());
System.out.println("--min time : " + waitingTimeStats.getMinTime());
System.out.println("--max time : " + waitingTimeStats.getMaxTime());
}
}
}
JVM Info 모니터링 예제는 JEUS의 노드 또는 컨테이너의 JVM에 대해 모니터링을 한다. 이 예제를 통해 모니터하는 정보는 다음과 같다.
JVM의 Total size 정보
JVM의 Heap size 정보
JVM의 Uptime 정보
다음은 JVM Info 모니터링 예제이다.
package monitoring;
import java.util.Iterator;
import java.util.Set;
import javax.management.MBeanServerConnection;
import javax.management.MBeanServerInvocationHandler;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.j2ee.statistics.BoundedRangeStatistic;
import javax.management.j2ee.statistics.CountStatistic;
import javax.management.j2ee.statistics.RangeStatistic;
import jeus.management.j2ee.JVMMBean;
import jeus.management.j2ee.statistics.JVMStatsImpl;
public class JVMInfo {
public void showInfo(MBeanServerConnection mBeanServer, String targetName)
throws Exception {
System.out.println("=== JVM Statistics ===");
ObjectName objectName = new ObjectName("JEUS:j2eeType=JVM,name="
+ targetName + ",*");
Set jvmMBeans = mBeanServer.queryMBeans(objectName, null);
for (Iterator i = jvmMBeans.iterator(); i.hasNext();) {
ObjectName objName = ((ObjectInstance) i.next()).getObjectName();
System.out.println("[MBean] " + objName);
// JVMMBean Stats
JVMMBean jvm = (JVMMBean)MBeanServerInvocationHandler.newProxyInstance(
mBeanServer, objName, JVMMBean.class, false);
JVMStatsImpl jvmstatsimpl = (JVMStatsImpl) jvm.getstats();
RangeStatistic totalSize = jvmstatsimpl.getTotalSize();
BoundedRangeStatistic heapSize = jvmstatsimpl.getHeapSize();
CountStatistic upTime = jvmstatsimpl.getUpTime();
// JVM Total Size
System.out.println("[Total Size]");
System.out.println("-unit : " + totalSize.getUnit());
System.out.println("-current : " + totalSize.getCurrent());
System.out.println("-min size : " + totalSize.getLowWaterMark());
System.out.println("-max size : " + totalSize.getHighWaterMark());
// JVM Heap Size
System.out.println("[Heap Size]");
System.out.println("-unit : " + heapSize.getUnit());
System.out.println("-current : " + heapSize.getCurrent());
System.out.println("-min Size : " + heapSize.getLowWaterMark());
System.out.println("-max Size : " + heapSize.getHighWaterMark());
System.out.println("-lower bound : " + heapSize.getLowerBound());
System.out.println("-upper bound : " + heapSize.getUpperBound());
// JVM UpTime
System.out.println("[Up Time]");
System.out.println("-unit : " + upTime.getUnit());
System.out.println("-count : " + upTime.getCount());
System.out.println("-start time : " + upTime.getStartTime());
}
}
}
본 절에서 설명하는 예제는 서버에 존재하는 DB Connection Pool을 모니터링한다. 여기에는 javax.management.remote.JMXConnector을 이용하여 MBean Connection을 얻는 예제도 함께 포함되어 있다.
이 예제의 내용은 다음과 같다.
특정 서버의 MBean 서버로 연결한다.
jeus.management.j2ee.JDBCResourceMBean을 조회해서 현재 생성된 Connection Pool들의 정보를 주기적으로 파일에 남긴다.
Connection Pool은 기동할 때 생성되지 않고 실제 서비스 호출 시점에 생성된다.
다음은 DB Connection Pool 모니터링 예제이다.
package monitoring;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Set;
import javax.management.MBeanServerConnection;
import javax.management.MBeanServerInvocationHandler;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.j2ee.statistics.JDBCConnectionPoolStats;
import javax.management.j2ee.statistics.JDBCStats;
import javax.management.remote.JMXConnector;
import javax.naming.Context;
import javax.naming.InitialContext;
import jeus.management.JMXConstants;
import jeus.management.j2ee.JDBCResourceMBean;
public class DBStatsClient {
public static void main(String[] args) {
String serverName = "changeplz"; //e.g. server1
Hashtable<String, Object> env = new Hashtable<String,Object>();
env.put(Context.INITIAL_CONTEXT_FACTORY, "jeus.jndi.JNSContextFactory");
env.put(Context.URL_PKG_PREFIXES, "jeus.jndi.jns.url");
env.put(Context.PROVIDER_URL, "localhost:9736");
MBeanServerConnection mbsc;
try {
InitialContext ctx = new InitialContext(env);
JMXConnector connector = (JMXConnector)ctx.lookup(
JMXConstants.JNDI_BINDING_PREFIX + serverName);
connector.connect();
mbsc = connector.getMBeanServerConnection();
} catch (Exception e) {
e.printStackTrace();
return;
}
System.out.println("mbean server connection successfully established");
Set mbeans;
try {
ObjectName dbstats = new ObjectName("JEUS:j2eeType=JDBCResource,*");
mbeans = mbsc.queryMBeans(dbstats, null);
} catch (Exception e) {
e.printStackTrace();
return;
}
System.out.println("Successfully get JDBCResource");
File file = new File(serverName+".log");
FileOutputStream stream = null;
try {
stream = new FileOutputStream(file);
} catch (IOException e) {
e.printStackTrace();
return;
}
while(true) {
for (Iterator iter = mbeans.iterator();iter.hasNext();) {
ObjectName jdbcResourceMBeanName =
((ObjectInstance) iter.next()).getObjectName();
JDBCResourceMBean jdbcResource =
(JDBCResourceMBean) MBeanServerInvocationHandler.newProxyInstance(
mbsc, jdbcResourceMBeanName,
JDBCResourceMBean.class, false);
JDBCStats jdbcStats = (JDBCStats) jdbcResource.getstats();
SimpleDateFormat format = new SimpleDateFormat("[MM-dd]HH:mm:ss");
StringBuilder builder = new StringBuilder();
builder.append("[STA] ");
for (JDBCConnectionPoolStats cpStats : jdbcStats.getConnectionPools())
{
String output =format.format(new Date(System.currentTimeMillis()))
+ " name:[" +cpStats.getJdbcDataSource() + "]"
+ " total:[" +cpStats.getPoolSize().getCurrent() +"]"
+ " use:[" + (cpStats.getPoolSize().getCurrent()
- cpStats.getFreePoolSize().getCurrent()) +"] ";
builder.append(output);
}
builder.append("\n");
try {
stream.write(builder.toString().getBytes());
} catch (IOException e) {
e.printStackTrace();
return;
}
}
try {
Thread.sleep(10000);
} catch (InterruptedException e) {
return;
}
}
}
}