我有一个简单的Java多线程回显服务器代码(它将接收到的内容返回给客户端)。 我正在对服务器的各种资源进行性能分析,包括线程统计信息。 下面是一些这些统计数据,根据连接的客户端数量。我的问题是与基线(客户端数为0)相比非基线是什么!
1)为什么当单个客户端连接时,总线程数会增加2?(对于其他情况,递增1是有意义的)
2)这两个非守护进程线程是什么?为什么守护线程最初递增1,然后保持不变?
它们是某种随机类型吗?!
# clients 0 1 2 3 4 5 6 7 8 9 10
Total Started Thread Count 15 18 19 20 21 22 23 24 25 26 27
Thread count 14 16 17 18 19 20 21 22 23 24 25
Peak thread count 14 16 17 18 19 20 21 22 23 24 25
Daemon thread count 12 13 13 13 13 13 13 13 13 13 13
这是服务器代码的片段。我同时使用了RMI(用于客户端轮询消息)和Server Socket(用于客户端发送消息)。如果需要其他类,请告诉我。
package test;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.rmi.server.UnicastRemoteObject;
import java.util.Vector;
public class ServerRMI extends Thread implements Hello {
//centralized token manager runs polling server and socket server to receive updated tokens
static Vector<String> tokenList= new Vector<String>();
protected Socket clientSocket;
static int RMIRegistryPort=9001;
static int SocketServerPort=9010;
public static void main(String[] args) throws IOException {
try {
ServerRMI obj = new ServerRMI();
Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);
// Bind the remote object's stub in the registry
Registry registry = LocateRegistry.createRegistry(RMIRegistryPort);
registry.bind("Hello", stub);
System.err.println("Server ready");
} catch (Exception e) {
System.err.println("Server exception: " + e.toString());
e.printStackTrace();
}
ServerSocket serverSocket = null;
//initialize token list
//A needs to execute first
tokenList.add(0,"0");
try {
serverSocket = new ServerSocket(SocketServerPort);
System.out.println("Connection Socket Created");
try {
while (true) {
System.out.println("Waiting for Connection");
new ServerRMI(serverSocket.accept());
}
} catch (IOException e) {
System.err.println("Accept failed.");
}
} catch (IOException e) {
System.err.println("Could not listen on port: "+SocketServerPort);
} finally {
try {
serverSocket.close();
} catch (IOException e) {
System.err.println("Could not close port: "+SocketServerPort);
}
}
}
private ServerRMI(Socket clientSoc) {
clientSocket = clientSoc;
start();
}
public ServerRMI() {}{
// TODO Auto-generated constructor stub
}
public void run() {
System.out.println("New Communication Thread Started");
try {
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(),
true);
BufferedReader in = new BufferedReader(new InputStreamReader(
clientSocket.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
tokenList.add(0,inputLine);
System.out.println("Server received: " + inputLine);
// System.out.println(" ququ size: "+queue.size());
out.println(inputLine);
if (inputLine.equals("Bye."))
break;
}
out.close();
in.close();
clientSocket.close();
} catch (IOException e) {
System.err.println("Problem with Communication Server");
}
}
public String pollServer() {
if(!tokenList.isEmpty()){
String data = tokenList.get(0);
System.out.println("Poll data: "+data);
return data;
} else{
return tokenList.size()+"";
}
}
}
jconsole
或jvisualvm
会在“线程”选项卡中显示所有线程信息。 在进程中还会运行一些分析器线程,这将增加计数。 - Pradhan