有人能发现内存泄漏吗？

时间：2010-09-13 19:42:16

标签： java memory memory-leaks

你好我一直试图找到这个内存泄漏一段时间而且没有运气。

我所拥有的服务器是为闪存客户端安全接受提供服务的。它只发送一个数据包，但有权保持超过10,000个并发连接？也许是65,534，如果它也有。

无论如何，在24小时内为210,000多名用户提供服务后，内存使用量从12,000 MB增加到74,000 MB。我认为它会稳定在那并保持思考可能它的一些东西已经解压缩注册并将被重新使用。但是48小时之后它达到了90 MB并且按照这个速度我将不得不每2天重新启动一次服务器以防止OutOfMemoryException（还没有得到它但我知道我只需要300 MB的ram来备用它）。

无论如何，如果有人有任何时间并想帮助我，我真的很感激，这里是来源。

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CodingErrorAction;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.channels.spi.SelectorProvider;
import java.util.*;

public class PolicyServer implements Runnable {
    public static final String POLICY_REQUEST = "<policy-file-request/>";
    public static final String POLICY_XML =
        "<?xml version=\"1.0\"?>"
        + "<cross-domain-policy>"
        + "<allow-access-from domain=\"*\" to-ports=\"*\" />"
        + "</cross-domain-policy>"
        + (char)0;


    // The host:port combination to listen on
    private InetAddress hostAddress;
    private int port;

    // The channel on which we'll accept connections
    private ServerSocketChannel serverChannel;

    // The selector we'll be monitoring
    private Selector selector;

    // The buffer into which we'll read data when it's available
    private ByteBuffer readBuffer = ByteBuffer.allocate(255);

    // This decodes raw bytes into ascii data.
    private CharsetDecoder asciiDecoder;

    // A list of PendingChange instances
    private List<ChangeRequest> pendingChanges = new LinkedList<ChangeRequest>();

    // Maps a SocketChannel to a list of ByteBuffer instances
    private Map<SocketChannel, List<ByteBuffer>> pendingData = new HashMap<SocketChannel, List<ByteBuffer>>();

    public PolicyServer(InetAddress hostAddress, int port) throws IOException {
        this.hostAddress = hostAddress;
        this.port = port;
        this.selector = this.initSelector();
        this.asciiDecoder = Charset.forName("US-ASCII").newDecoder().onMalformedInput(
                                CodingErrorAction.REPLACE).onUnmappableCharacter(
                                CodingErrorAction.REPLACE);
    }

    public void send(SocketChannel socket, byte[] data) {
        synchronized (this.pendingChanges) {
            // Indicate we want the interest ops set changed
            this.pendingChanges.add(new ChangeRequest(socket, ChangeRequest.CHANGEOPS, SelectionKey.OP_WRITE));

            // And queue the data we want written
            synchronized (this.pendingData) {
                List<ByteBuffer> queue = (List<ByteBuffer>) this.pendingData.get(socket);
                if (queue == null) {
                    queue = new ArrayList<ByteBuffer>();
                    this.pendingData.put(socket, queue);
                }
                queue.add(ByteBuffer.wrap(data));
            }
        }

        // Finally, wake up our selecting thread so it can make the required changes
        this.selector.wakeup();
    }

    public void run() {
        while (true) {
            try {
                // Process any pending changes
                synchronized (this.pendingChanges) {
                    Iterator changes = this.pendingChanges.iterator();
                    while (changes.hasNext()) {
                        ChangeRequest change = (ChangeRequest) changes.next();
                        if(change == null) continue;
                        switch (change.type) {
                        case ChangeRequest.CHANGEOPS:
                            SelectionKey key = change.socket.keyFor(this.selector);
                            try {
                                if(key!=null)
                                    key.interestOps(change.ops);
                            } catch(Exception ex) {
                                if (key!=null)
                                    key.cancel();
                            }
                        }
                    }
                    this.pendingChanges.clear();
                }

                // Wait for an event one of the registered channels
                this.selector.select();

                // Iterate over the set of keys for which events are available
                Iterator selectedKeys = this.selector.selectedKeys().iterator();
                while (selectedKeys.hasNext()) {
                    SelectionKey key = (SelectionKey) selectedKeys.next();
                    selectedKeys.remove();

                    if (!key.isValid()) {
                        continue;
                    }

                    // Check what event is available and deal with it
                    if (key.isAcceptable()) {
                        this.accept(key);
                    } else if (key.isReadable()) {
                        this.read(key);
                    } else if (key.isWritable()) {
                        this.write(key);
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    private void accept(SelectionKey key) throws IOException {
        // For an accept to be pending the channel must be a server socket channel.
        ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel();

        // Accept the connection and make it non-blocking
        SocketChannel socketChannel = serverSocketChannel.accept();
        Socket socket = socketChannel.socket();
        socketChannel.configureBlocking(false);

        // Register the new SocketChannel with our Selector, indicating
        // we'd like to be notified when there's data waiting to be read
        // also contains a attachment of a new StringBuffer (for storing imcomplete/multi packets)
        socketChannel.register(this.selector, SelectionKey.OP_READ, new StringBuffer());
    }

    private void read(SelectionKey key) throws IOException {
        SocketChannel socketChannel = (SocketChannel) key.channel();

        // Clear out our read buffer so it's ready for new data
        this.readBuffer.clear();

        // Attempt to read off the channel
        int numRead;
        try {
            numRead = socketChannel.read(this.readBuffer);
        } catch (IOException e) {
            // The remote forcibly closed the connection, cancel
            // the selection key and close the channel.
            key.cancel();
            socketChannel.close();
            return;
        }

        if (numRead == -1) {
            // Remote entity shut the socket down cleanly. Do the
            // same from our end and cancel the channel.
            key.channel().close();
            key.cancel();
            return;
        }

        // Grab the StringBuffer we stored as the attachment
        StringBuffer sb = (StringBuffer)key.attachment();

        // Flips the readBuffer by setting the current position of
        // packet stream to beginning.
        // Append the data to the attachment StringBuffer
        this.readBuffer.flip();
        sb.append(this.asciiDecoder.decode(this.readBuffer).toString());
        this.readBuffer.clear();

        // Get the policy request as complete packet
        if(sb.indexOf("\0") != -1) {
            String packets = sb.substring(0, sb.lastIndexOf("\0")+1);
            sb.delete(0, sb.lastIndexOf("\0")+1);

            if(packets.indexOf(POLICY_REQUEST) != -1)
                send(socketChannel, POLICY_XML.getBytes());
        }
    }

    private void write(SelectionKey key) throws IOException {
        SocketChannel socketChannel = (SocketChannel) key.channel();

        synchronized (this.pendingData) {
            List queue = (List) this.pendingData.get(socketChannel);

            // Write until there's not more data ...
            while (!queue.isEmpty()) {
                ByteBuffer buf = (ByteBuffer) queue.get(0);
                try {
                    socketChannel.write(buf);
                    if (buf.remaining() > 0) {
                        // ... or the socket's buffer fills up
                        break;
                    }
                } catch(IOException e) {
                    // The remote forcibly closed the connection, cancel
                    // the selection key and close the channel.
                    key.cancel();
                    socketChannel.close();
                    return;
                }
                queue.remove(0);
            }

            if (queue.isEmpty()) {
                // We wrote away all data, so we're no longer interested
                // in writing on this socket. Switch back to waiting for
                // data.
                try {
                    if (key!=null)
                        key.interestOps(SelectionKey.OP_READ);
                } catch(Exception ex) {
                    if (key!=null)
                        key.cancel();
                }
            }
        }
    }

    private Selector initSelector() throws IOException {
        // Create a new selector
        Selector socketSelector = SelectorProvider.provider().openSelector();

        // Create a new non-blocking server socket channel
        this.serverChannel = ServerSocketChannel.open();
        serverChannel.configureBlocking(false);

        // Bind the server socket to the specified address and port
        InetSocketAddress isa = new InetSocketAddress(this.hostAddress, this.port);
        serverChannel.socket().bind(isa);

        // Register the server socket channel, indicating an interest in
        // accepting new connections
        serverChannel.register(socketSelector, SelectionKey.OP_ACCEPT);

        return socketSelector;
    }

    public static void main(String[] args) {
        try {
            new Thread(new PolicyServer(null, 5556)).start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

这是ChangeRequest类

import java.nio.channels.SocketChannel;

public class ChangeRequest {
    public static final int REGISTER = 1;
    public static final int CHANGEOPS = 2;

    public SocketChannel socket;
    public int type;
    public int ops;

    public ChangeRequest(SocketChannel socket, int type, int ops) {
        this.socket = socket;
        this.type = type;
        this.ops = ops;
    }
}

5 个答案:

答案 0 :(得分：2)

可能不是唯一的问题，但我认为您不会致电pendingChanges.remove()

此外，您应该尝试使用分析器 - 它比手动审查更容易。

答案 1 :(得分：1)

你班上有几个收藏品：

private List<ChangeRequest> pendingChanges = ...;
private Map<SocketChannel, List<ByteBuffer>> pendingData = ...;

这些将是我的第一个检查目标 - 这些是否随着时间的推移不断增长？你是否正确删除未使用的元素？在适当的地方进行一些调试打印输出应该能够给你答案......

如果这不能给你一个明显的解决方案，那么我对于尝试使用内存分析器的看法很重要。

答案 2 :(得分：1)

如果你有Java5或更高版本，请加载JConsole（在％JAVA_HOME％/ bin / dir中），它将列出它可以找到的正在运行的java进程。连接到您的应用程序。并且有一个按钮用于执行垃圾收集。

我怀疑这不是内存泄漏，而是将内存分配给旧版本。通过执行手动垃圾收集，您将执行完整的GC，这将清除它。如果它是一个真正的内存泄漏，那么大多数（如果不是全部）这些内存都会挂起。

如果这是内存泄漏，请注意使用列表，地图等。确保在用户访问时添加信息，并在信息被删除时将其销毁。

答案 3 :(得分：0)

你是否隐瞒任何连接？

如果与远程计算机建立连接，并且变量超出范围，则它仍处于活动状态，并且在连接中断（由另一方或网络故障）之前不会进行垃圾收集。

答案 4 :(得分：0)

这是我到目前为止所发现的。

运行快速黑客数据包垃圾邮件应用程序后

import java.io.*;
import java.util.*;
import java.net.*;
public class Spam {

public static final String POLICY_REQUEST = "<policy-file-request/>";
public static int sbyte;
    public static void main(String args[]) {
        while(true) {
            try {
                Socket s = new Socket("127.0.0.1", 5556);
                PrintWriter out = new PrintWriter(s.getOutputStream(), true);
                        BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
                out.println(POLICY_REQUEST+(char)0);
                                while(s.getInputStream().available() > 0)
                  sbyte = in.read();
                                //Simulate never closing connection. or until Timeout
                //out.close();
                //in.close();
                //s.close();
            } catch(UnknownHostException uhe) {
            } catch(Exception e) {
            }
        }

    }
}

在readerBuffer.clear

下的PolicyServer中为read（）添加了输出 
    System.out.println("Total pendingChanges = " + this.pendingChanges.size());
    System.out.println("Total pendingData = " + this.pendingData.size());
    System.out.println("Total sb = " + sb.length());

这是输出

Total pendingChanges = 0
Total pendingData = 0
Total sb = 25
Total pendingChanges = 0
Total pendingData = 1
Total sb = 25
Total pendingChanges = 0
Total pendingData = 2
Total sb = 25
Total pendingChanges = 0
Total pendingData = 3
Total sb = 25
Total pendingChanges = 0
Total pendingData = 4
Total sb = 25
Total pendingChanges = 0
Total pendingData = 5
Total sb = 25
Total pendingChanges = 0
Total pendingData = 6
Total sb = 25
Total pendingChanges = 0
Total pendingData = 7
Total sb = 25
Total pendingChanges = 0
Total pendingData = 8
Total sb = 25
Total pendingChanges = 0
Total pendingData = 9
Total sb = 25
Total pendingChanges = 0
Total pendingData = 10
Total sb = 25
Total pendingChanges = 0
Total pendingData = 11
Total sb = 25
Total pendingChanges = 0
Total pendingData = 12
Total sb = 25
Total pendingChanges = 0
Total pendingData = 13
Total sb = 25
Total pendingChanges = 0
Total pendingData = 14
Total sb = 25
Total pendingChanges = 0
Total pendingData = 15
Total sb = 25
Total pendingChanges = 0
Total pendingData = 16
Total sb = 25
Total pendingChanges = 0
Total pendingData = 17
Total sb = 25
Total pendingChanges = 0
Total pendingData = 18
Total sb = 25
Total pendingChanges = 0
Total pendingData = 19
Total sb = 25
Total pendingChanges = 0
Total pendingData = 20
Total sb = 25
Total pendingChanges = 0
Total pendingData = 21
Total sb = 25
Total pendingChanges = 0
Total pendingData = 22
Total sb = 25
Total pendingChanges = 0
Total pendingData = 23
Total sb = 25
Total pendingChanges = 0
Total pendingData = 24
Total sb = 25
Total pendingChanges = 0
Total pendingData = 25
Total sb = 25
Total pendingChanges = 0
Total pendingData = 26
Total sb = 25
Total pendingChanges = 0
Total pendingData = 27
Total sb = 25
Total pendingChanges = 0
Total pendingData = 28
Total sb = 25
Total pendingChanges = 0
Total pendingData = 29
Total sb = 25
Total pendingChanges = 0
Total pendingData = 30
Total sb = 25
Total pendingChanges = 0
Total pendingData = 31
Total sb = 25
Total pendingChanges = 0
Total pendingData = 32
Total sb = 25
Total pendingChanges = 0
Total pendingData = 33
Total sb = 25
Total pendingChanges = 0
Total pendingData = 34
Total sb = 25
Total pendingChanges = 0
Total pendingData = 35
Total sb = 25
Total pendingChanges = 0
Total pendingData = 36
Total sb = 25
Total pendingChanges = 0
Total pendingData = 37
Total sb = 25
Total pendingChanges = 0
Total pendingData = 38
Total sb = 25
Total pendingChanges = 0
Total pendingData = 39
Total sb = 25
Total pendingChanges = 0
Total pendingData = 40
Total sb = 25
Total pendingChanges = 0
Total pendingData = 41
Total sb = 25
Total pendingChanges = 0
Total pendingData = 42
Total sb = 25
Total pendingChanges = 0
Total pendingData = 43
Total sb = 25
Total pendingChanges = 0
Total pendingData = 44
Total sb = 25
Total pendingChanges = 0
Total pendingData = 45
Total sb = 25
Total pendingChanges = 0
Total pendingData = 46
Total sb = 25
Total pendingChanges = 0
Total pendingData = 47
Total sb = 25
Total pendingChanges = 0
Total pendingData = 48
Total sb = 25
Total pendingChanges = 0
Total pendingData = 49
Total sb = 25
Total pendingChanges = 0
Total pendingData = 50
Total sb = 25
Total pendingChanges = 0
Total pendingData = 51
Total sb = 25
Total pendingChanges = 0
Total pendingData = 52
Total sb = 25
Total pendingChanges = 0
Total pendingData = 53
Total sb = 25
Total pendingChanges = 0
Total pendingData = 54
Total sb = 25
Total pendingChanges = 0
Total pendingData = 55
Total sb = 25
Total pendingChanges = 0
Total pendingData = 56
Total sb = 25
Total pendingChanges = 0
Total pendingData = 57
Total sb = 25
Total pendingChanges = 0
Total pendingData = 58
Total sb = 25
Total pendingChanges = 0
Total pendingData = 59
Total sb = 25
Total pendingChanges = 0
Total pendingData = 60
Total sb = 25
Total pendingChanges = 0
Total pendingData = 61
Total sb = 25
Total pendingChanges = 0
Total pendingData = 62
Total sb = 25
Total pendingChanges = 0
Total pendingData = 63
Total sb = 25
Total pendingChanges = 0
Total pendingData = 64
Total sb = 25
Total pendingChanges = 0
Total pendingData = 65
Total sb = 25
Total pendingChanges = 0
Total pendingData = 66
Total sb = 25
Total pendingChanges = 0
Total pendingData = 67
Total sb = 25
Total pendingChanges = 0
Total pendingData = 68
Total sb = 25
Total pendingChanges = 0
Total pendingData = 69
Total sb = 25
Total pendingChanges = 0
Total pendingData = 70
Total sb = 25
Total pendingChanges = 0
Total pendingData = 71
Total sb = 25
Total pendingChanges = 0
Total pendingData = 72
Total sb = 25
Total pendingChanges = 0
Total pendingData = 73
Total sb = 25
Total pendingChanges = 0
Total pendingData = 74
Total sb = 25
Total pendingChanges = 0
Total pendingData = 75
Total sb = 25
Total pendingChanges = 0
Total pendingData = 76
Total sb = 25
Total pendingChanges = 0
Total pendingData = 77
Total sb = 25
Total pendingChanges = 0
Total pendingData = 78
Total sb = 25
Total pendingChanges = 0
Total pendingData = 79
Total sb = 25
Total pendingChanges = 0
Total pendingData = 80
Total sb = 25
Total pendingChanges = 0
Total pendingData = 81
Total sb = 25
Total pendingChanges = 0
Total pendingData = 82
Total sb = 25
Total pendingChanges = 0
Total pendingData = 83
Total sb = 25
Total pendingChanges = 0
Total pendingData = 84
Total sb = 25
Total pendingChanges = 0
Total pendingData = 85
Total sb = 25
Total pendingChanges = 0
Total pendingData = 86
Total sb = 25
Total pendingChanges = 0
Total pendingData = 87
Total sb = 25
Total pendingChanges = 0
Total pendingData = 88
Total sb = 25
Total pendingChanges = 0
Total pendingData = 89
Total sb = 25
Total pendingChanges = 0
Total pendingData = 90
Total sb = 25
Total pendingChanges = 0
Total pendingData = 91
Total sb = 25
Total pendingChanges = 0
Total pendingData = 92
Total sb = 25
Total pendingChanges = 0
Total pendingData = 93
Total sb = 25
Total pendingChanges = 0
Total pendingData = 94
Total sb = 25
Total pendingChanges = 0
Total pendingData = 95
Total sb = 25
Total pendingChanges = 0
Total pendingData = 96
Total sb = 25
Total pendingChanges = 0
Total pendingData = 97
Total sb = 25
Total pendingChanges = 0
Total pendingData = 98
Total sb = 25
Total pendingChanges = 0
Total pendingData = 99
Total sb = 25
Total pendingChanges = 0
Total pendingData = 100
Total sb = 25
Total pendingChanges = 0
Total pendingData = 101
Total sb = 25
Total pendingChanges = 0
Total pendingData = 102
Total sb = 25
Total pendingChanges = 0
Total pendingData = 103
Total sb = 25
Total pendingChanges = 0
Total pendingData = 104
Total sb = 25
Total pendingChanges = 0
Total pendingData = 105
Total sb = 25
Total pendingChanges = 0
Total pendingData = 106
Total sb = 25
Total pendingChanges = 0
Total pendingData = 107
Total sb = 25
Total pendingChanges = 0
Total pendingData = 108
Total sb = 25
Total pendingChanges = 0
Total pendingData = 109
Total sb = 25
Total pendingChanges = 0
Total pendingData = 110
Total sb = 25
Total pendingChanges = 0
Total pendingData = 111
Total sb = 25
Total pendingChanges = 0
Total pendingData = 112
Total sb = 25
Total pendingChanges = 0
Total pendingData = 113
Total sb = 25
Total pendingChanges = 0
Total pendingData = 114
Total sb = 25
Total pendingChanges = 0
Total pendingData = 115
Total sb = 25
Total pendingChanges = 0
Total pendingData = 116
Total sb = 25
Total pendingChanges = 0
Total pendingData = 117
Total sb = 25
Total pendingChanges = 0
Total pendingData = 118
Total sb = 25
Total pendingChanges = 0
Total pendingData = 119
Total sb = 25
Total pendingChanges = 0
Total pendingData = 120
Total sb = 25
Total pendingChanges = 0
Total pendingData = 121
Total sb = 25
Total pendingChanges = 0
Total pendingData = 122
Total sb = 25
Total pendingChanges = 0
Total pendingData = 123
Total sb = 25
Total pendingChanges = 0
Total pendingData = 124
Total sb = 25
Total pendingChanges = 0
Total pendingData = 125
Total sb = 25
Total pendingChanges = 0
Total pendingData = 126
Total sb = 25
Total pendingChanges = 0
Total pendingData = 127
Total sb = 25
Total pendingChanges = 0
Total pendingData = 128
Total sb = 25
Total pendingChanges = 0
Total pendingData = 129
Total sb = 25
Total pendingChanges = 0
Total pendingData = 130
Total sb = 25
Total pendingChanges = 0
Total pendingData = 131
Total sb = 25
Total pendingChanges = 0
Total pendingData = 132
Total sb = 25
Total pendingChanges = 0
Total pendingData = 133
Total sb = 25
Total pendingChanges = 0
Total pendingData = 134
Total sb = 25
Total pendingChanges = 0
Total pendingData = 135
Total sb = 25
Total pendingChanges = 0
Total pendingData = 136
Total sb = 25
Total pendingChanges = 0
Total pendingData = 137
Total sb = 25
Total pendingChanges = 0
Total pendingData = 138
Total sb = 25
Total pendingChanges = 0
Total pendingData = 139
Total sb = 25
Total pendingChanges = 0
Total pendingData = 140
Total sb = 25
Total pendingChanges = 0
Total pendingData = 141
Total sb = 25
Total pendingChanges = 0
Total pendingData = 142
Total sb = 25
Total pendingChanges = 0
Total pendingData = 143
Total sb = 25
Total pendingChanges = 0
Total pendingData = 144
Total sb = 25
Total pendingChanges = 0
Total pendingData = 145
Total sb = 25
Total pendingChanges = 0
Total pendingData = 146
Total sb = 25
Total pendingChanges = 0
Total pendingData = 147
Total sb = 25
Total pendingChanges = 0
Total pendingData = 148
Total sb = 25
Total pendingChanges = 0
Total pendingData = 149
Total sb = 25
Total pendingChanges = 0
Total pendingData = 150
Total sb = 25
Total pendingChanges = 0
Total pendingData = 151
Total sb = 25
Total pendingChanges = 0
Total pendingData = 152
Total sb = 25
Total pendingChanges = 0
Total pendingData = 153
Total sb = 25
Total pendingChanges = 0
Total pendingData = 154
Total sb = 25
Total pendingChanges = 0
Total pendingData = 155
Total sb = 25
Total pendingChanges = 0
Total pendingData = 156
Total sb = 25
Total pendingChanges = 0
Total pendingData = 157
Total sb = 25
Total pendingChanges = 0
Total pendingData = 158
Total sb = 25
Total pendingChanges = 0
Total pendingData = 159
Total sb = 25
Total pendingChanges = 0
Total pendingData = 160
Total sb = 25
相关问题
最新问题