Hi Adrew/Filip,
I guess I am in similar situation as Andrew, I am trying to monitor
my application through nagios and I was about to start writing a plugin to
monitor AJP Queue size. I thought I could use andrews solution, but I am
still unsure of the state of the patch he contributed and whether I can use
that patch and customize and create a plugin for the same.
Appreciate your responses.
Thanks
Sri
Andrew Skiba-2 wrote:
>
> Hello,
>
> I want to contribute a custom SocketFactory allowing to analyze the
> utilization of acceptConnection attribute of a Connector. In a properly
> configured production system, there should be rare situations where
> connections wait for a worker thread to be handled. Our client complained
> on
> high latency of web requests, but the measurement on servlet did not show
> high latency. So we wanted to know the number of connections which wait in
> socket backlog and were not accepted yet.
>
> I solved this problem by writing a custom SocketFactory, which accepts
> connections immediately and puts it in my queue until a call to accept()
> will take them. So the number of waiting connections can be monitored via
> JMX.
>
> To activate this factory, the declaration of the corresponding Connector
> in
> server.xml should be changed like in the following example.
>
> <Connector port="8080" maxHttpHeaderSize="8192"
> maxThreads="10" minSpareThreads="5" maxSpareThreads="7"
> enableLookups="false" redirectPort="8443" acceptCount="10"
> connectionTimeout="2000" disableUploadTimeout="true"
>
> socketFactory="
> org.apache.tomcat.util.net.BacklogMeasuringServerSocketFactory"/>
>
>
> No changes in existing classes are required.
>
> Please review the code in the attachment.
>
>
> Andrew Skiba.
>
>
> package org.apache.tomcat.util.net;
>
> import java.io.*;
> import java.net.*;
> import java.util.concurrent.BlockingQueue;
> import java.util.concurrent.LinkedBlockingQueue;
> import java.util.concurrent.atomic.AtomicLong;
> import javax.management.MBeanRegistration;
> import javax.management.MBeanServer;
> import javax.management.ObjectName;
> import org.apache.commons.modeler.Registry;
>
> /**
> * Default server socket factory. Doesn't do much except give us
> * plain ol' server sockets.
> *
> * @author [EMAIL PROTECTED]
> * @author Harish Prabandham
> */
>
> // Default implementation of server sockets.
>
> //
> // WARNING: Some of the APIs in this class are used by J2EE.
> // Please talk to [EMAIL PROTECTED] before making any changes.
> //
> public class BacklogMeasuringServerSocketFactory extends
> ServerSocketFactory
> implements MBeanRegistration
> {
> private static org.apache.commons.logging.Log logger =
>
> org.apache.commons.logging.LogFactory.getLog(BacklogMeasuringServerSocketFactory.class);
> private static AtomicLong queuesCommonSize = new AtomicLong(0);
>
> static class ServerSocketProxy extends ServerSocket {
> public static final int DEFAULT_QUEUE_SIZE = 50;
>
> BlockingQueue<Socket> acceptQueue;
> Thread acceptThread;
>
> class AcceptRunnable implements Runnable {
> public void run() {
> try {
> while (!isClosed()) {
> acceptQueue.put(superAccept());
> queuesCommonSize.incrementAndGet();
> }
> } catch (InterruptedException ex) {
> logger.warn("unexpected exception", ex);
> } catch (IOException ex) {
> logger.info("stopping accepting connections", ex);
> }
> }
> }
>
> private Socket superAccept () throws IOException {
> return super.accept();
> }
> void init (int queueSize) {
> acceptQueue = new LinkedBlockingQueue (queueSize);
> acceptThread = new Thread(new AcceptRunnable(),
> "Accept-"+toString());
> acceptThread.start();
> }
>
> public ServerSocketProxy(int port) throws IOException {
> super(port);
> init(DEFAULT_QUEUE_SIZE);
> }
>
> public ServerSocketProxy(int port, int backlog) throws IOException
> {
> super(port, backlog);
> init(backlog);
> }
>
> public ServerSocketProxy(int port, int backlog, InetAddress
> bindAddr) throws IOException {
> super(port, backlog, bindAddr);
> init(backlog);
> }
>
> @Override
> public Socket accept() throws IOException {
> try {
> Socket res = acceptQueue.take();
> queuesCommonSize.decrementAndGet();
> return res;
> } catch (InterruptedException ex) {
> throw new SocketException ("unexpected
> InterruptedException");
> }
> }
> }
>
> public BacklogMeasuringServerSocketFactory () {
> try {
> Registry.getRegistry(null, null).registerComponent(this,
> new
> ObjectName("measure:type=Backlog,obj="+hashCode()), null);
> } catch (Exception ex) {
> logger.error("MBean was not registered", ex);
> }
> }
>
> public ServerSocket createSocket (int port)
> throws IOException {
> return new ServerSocketProxy(port);
> }
>
> public ServerSocket createSocket (int port, int backlog)
> throws IOException {
> return new ServerSocketProxy (port, backlog);
> }
>
> public ServerSocket createSocket (int port, int backlog,
> InetAddress ifAddress)
> throws IOException {
> return new ServerSocketProxy (port, backlog, ifAddress);
> }
>
> public Socket acceptSocket(ServerSocket socket)
> throws IOException {
> return socket.accept();
> }
>
> public void handshake(Socket sock)
> throws IOException {
> // NOOP
> }
>
> public long size () {
> return queuesCommonSize.longValue();
> }
>
>
> protected String domain;
> protected ObjectName oname;
> protected MBeanServer mserver;
>
> public ObjectName getObjectName() {
> return oname;
> }
>
> public String getDomain() {
> return domain;
> }
>
>
> public ObjectName preRegister(MBeanServer server, ObjectName name)
> throws Exception {
> this.oname = name;
> this.mserver = server;
> domain = name.getDomain();
> return name;
> }
>
> public void postRegister(Boolean registrationDone) {
> }
>
> public void preDeregister() throws Exception {
> }
>
> public void postDeregister() {
> }
> }
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
>
--
View this message in context:
http://www.nabble.com/backlog-measurement-tp14729968p16447208.html
Sent from the Tomcat - Dev mailing list archive at Nabble.com.
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
