| /** |
| * 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.hadoop.ipc; |
| |
| import java.io.IOException; |
| import java.io.DataInputStream; |
| import java.io.DataOutputStream; |
| import java.io.ByteArrayInputStream; |
| import java.io.ByteArrayOutputStream; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.channels.CancelledKeyException; |
| import java.nio.channels.ClosedChannelException; |
| import java.nio.channels.ReadableByteChannel; |
| import java.nio.channels.SelectionKey; |
| import java.nio.channels.Selector; |
| import java.nio.channels.ServerSocketChannel; |
| import java.nio.channels.SocketChannel; |
| import java.nio.channels.WritableByteChannel; |
| |
| import java.net.BindException; |
| import java.net.InetAddress; |
| import java.net.InetSocketAddress; |
| import java.net.ServerSocket; |
| import java.net.Socket; |
| import java.net.SocketException; |
| import java.net.UnknownHostException; |
| |
| import java.security.PrivilegedActionException; |
| import java.security.PrivilegedExceptionAction; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.Random; |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.LinkedBlockingQueue; |
| |
| import javax.security.auth.Subject; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.CommonConfigurationKeys; |
| import org.apache.hadoop.security.SecurityUtil; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.io.WritableUtils; |
| import org.apache.hadoop.util.ReflectionUtils; |
| import org.apache.hadoop.util.StringUtils; |
| import org.apache.hadoop.ipc.metrics.RpcMetrics; |
| import org.apache.hadoop.security.authorize.AuthorizationException; |
| |
| /** An abstract IPC service. IPC calls take a single {@link Writable} as a |
| * parameter, and return a {@link Writable} as their value. A service runs on |
| * a port and is defined by a parameter class and a value class. |
| * |
| * @see Client |
| */ |
| public abstract class Server { |
| |
| /** |
| * The first four bytes of Hadoop RPC connections |
| */ |
| public static final ByteBuffer HEADER = ByteBuffer.wrap("hrpc".getBytes()); |
| |
| // 1 : Introduce ping and server does not throw away RPCs |
| // 3 : Introduce the protocol into the RPC connection header |
| public static final byte CURRENT_VERSION = 3; |
| |
| /** |
| * Initial and max size of response buffer |
| */ |
| static int INITIAL_RESP_BUF_SIZE = 10240; |
| static int MAX_RESP_BUF_SIZE = 1024*1024; |
| |
| public static final Log LOG = LogFactory.getLog(Server.class); |
| |
| private static final ThreadLocal<Server> SERVER = new ThreadLocal<Server>(); |
| |
| private static final Map<String, Class<?>> PROTOCOL_CACHE = |
| new ConcurrentHashMap<String, Class<?>>(); |
| |
| static Class<?> getProtocolClass(String protocolName, Configuration conf) |
| throws ClassNotFoundException { |
| Class<?> protocol = PROTOCOL_CACHE.get(protocolName); |
| if (protocol == null) { |
| protocol = conf.getClassByName(protocolName); |
| PROTOCOL_CACHE.put(protocolName, protocol); |
| } |
| return protocol; |
| } |
| |
| /** Returns the server instance called under or null. May be called under |
| * {@link #call(Writable, long)} implementations, and under {@link Writable} |
| * methods of paramters and return values. Permits applications to access |
| * the server context.*/ |
| public static Server get() { |
| return SERVER.get(); |
| } |
| |
| /** This is set to Call object before Handler invokes an RPC and reset |
| * after the call returns. |
| */ |
| private static final ThreadLocal<Call> CurCall = new ThreadLocal<Call>(); |
| |
| /** Returns the remote side ip address when invoked inside an RPC |
| * Returns null incase of an error. |
| */ |
| public static InetAddress getRemoteIp() { |
| Call call = CurCall.get(); |
| if (call != null) { |
| return call.connection.socket.getInetAddress(); |
| } |
| return null; |
| } |
| /** Returns remote address as a string when invoked inside an RPC. |
| * Returns null in case of an error. |
| */ |
| public static String getRemoteAddress() { |
| InetAddress addr = getRemoteIp(); |
| return (addr == null) ? null : addr.getHostAddress(); |
| } |
| |
| private String bindAddress; |
| private int port; // port we listen on |
| private int handlerCount; // number of handler threads |
| private Class<? extends Writable> paramClass; // class of call parameters |
| private int maxIdleTime; // the maximum idle time after |
| // which a client may be disconnected |
| private int thresholdIdleConnections; // the number of idle connections |
| // after which we will start |
| // cleaning up idle |
| // connections |
| int maxConnectionsToNuke; // the max number of |
| // connections to nuke |
| //during a cleanup |
| |
| protected RpcMetrics rpcMetrics; |
| |
| private Configuration conf; |
| |
| private int maxQueueSize; |
| private int socketSendBufferSize; |
| private final boolean tcpNoDelay; // if T then disable Nagle's Algorithm |
| |
| volatile private boolean running = true; // true while server runs |
| private BlockingQueue<Call> callQueue; // queued calls |
| |
| private List<Connection> connectionList = |
| Collections.synchronizedList(new LinkedList<Connection>()); |
| //maintain a list |
| //of client connections |
| private Listener listener = null; |
| private Responder responder = null; |
| private int numConnections = 0; |
| private Handler[] handlers = null; |
| |
| /** |
| * A convenience method to bind to a given address and report |
| * better exceptions if the address is not a valid host. |
| * @param socket the socket to bind |
| * @param address the address to bind to |
| * @param backlog the number of connections allowed in the queue |
| * @throws BindException if the address can't be bound |
| * @throws UnknownHostException if the address isn't a valid host name |
| * @throws IOException other random errors from bind |
| */ |
| public static void bind(ServerSocket socket, InetSocketAddress address, |
| int backlog) throws IOException { |
| try { |
| socket.bind(address, backlog); |
| } catch (BindException e) { |
| BindException bindException = new BindException("Problem binding to " + address |
| + " : " + e.getMessage()); |
| bindException.initCause(e); |
| throw bindException; |
| } catch (SocketException e) { |
| // If they try to bind to a different host's address, give a better |
| // error message. |
| if ("Unresolved address".equals(e.getMessage())) { |
| throw new UnknownHostException("Invalid hostname for server: " + |
| address.getHostName()); |
| } else { |
| throw e; |
| } |
| } |
| } |
| |
| /** A call queued for handling. */ |
| private static class Call { |
| private int id; // the client's call id |
| private Writable param; // the parameter passed |
| private Connection connection; // connection to client |
| private long timestamp; // the time received when response is null |
| // the time served when response is not null |
| private ByteBuffer response; // the response for this call |
| |
| public Call(int id, Writable param, Connection connection) { |
| this.id = id; |
| this.param = param; |
| this.connection = connection; |
| this.timestamp = System.currentTimeMillis(); |
| this.response = null; |
| } |
| |
| @Override |
| public String toString() { |
| return param.toString() + " from " + connection.toString(); |
| } |
| |
| public void setResponse(ByteBuffer response) { |
| this.response = response; |
| } |
| } |
| |
| /** Listens on the socket. Creates jobs for the handler threads*/ |
| private class Listener extends Thread { |
| |
| private ServerSocketChannel acceptChannel = null; //the accept channel |
| private Selector selector = null; //the selector that we use for the server |
| private InetSocketAddress address; //the address we bind at |
| private Random rand = new Random(); |
| private long lastCleanupRunTime = 0; //the last time when a cleanup connec- |
| //-tion (for idle connections) ran |
| private long cleanupInterval = 10000; //the minimum interval between |
| //two cleanup runs |
| private int backlogLength = conf.getInt("ipc.server.listen.queue.size", 128); |
| |
| public Listener() throws IOException { |
| address = new InetSocketAddress(bindAddress, port); |
| // Create a new server socket and set to non blocking mode |
| acceptChannel = ServerSocketChannel.open(); |
| acceptChannel.configureBlocking(false); |
| |
| // Bind the server socket to the local host and port |
| bind(acceptChannel.socket(), address, backlogLength); |
| port = acceptChannel.socket().getLocalPort(); //Could be an ephemeral port |
| // create a selector; |
| selector= Selector.open(); |
| |
| // Register accepts on the server socket with the selector. |
| acceptChannel.register(selector, SelectionKey.OP_ACCEPT); |
| this.setName("IPC Server listener on " + port); |
| this.setDaemon(true); |
| } |
| /** cleanup connections from connectionList. Choose a random range |
| * to scan and also have a limit on the number of the connections |
| * that will be cleanedup per run. The criteria for cleanup is the time |
| * for which the connection was idle. If 'force' is true then all |
| * connections will be looked at for the cleanup. |
| */ |
| private void cleanupConnections(boolean force) { |
| if (force || numConnections > thresholdIdleConnections) { |
| long currentTime = System.currentTimeMillis(); |
| if (!force && (currentTime - lastCleanupRunTime) < cleanupInterval) { |
| return; |
| } |
| int start = 0; |
| int end = numConnections - 1; |
| if (!force) { |
| start = rand.nextInt() % numConnections; |
| end = rand.nextInt() % numConnections; |
| int temp; |
| if (end < start) { |
| temp = start; |
| start = end; |
| end = temp; |
| } |
| } |
| int i = start; |
| int numNuked = 0; |
| while (i <= end) { |
| Connection c; |
| synchronized (connectionList) { |
| try { |
| c = connectionList.get(i); |
| } catch (Exception e) {return;} |
| } |
| if (c.timedOut(currentTime)) { |
| if (LOG.isDebugEnabled()) |
| LOG.debug(getName() + ": disconnecting client " + c.getHostAddress()); |
| closeConnection(c); |
| numNuked++; |
| end--; |
| c = null; |
| if (!force && numNuked == maxConnectionsToNuke) break; |
| } |
| else i++; |
| } |
| lastCleanupRunTime = System.currentTimeMillis(); |
| } |
| } |
| |
| @Override |
| public void run() { |
| LOG.info(getName() + ": starting"); |
| SERVER.set(Server.this); |
| while (running) { |
| SelectionKey key = null; |
| try { |
| getSelector().select(); |
| Iterator<SelectionKey> iter = getSelector().selectedKeys().iterator(); |
| while (iter.hasNext()) { |
| key = iter.next(); |
| iter.remove(); |
| try { |
| if (key.isValid()) { |
| if (key.isAcceptable()) |
| doAccept(key); |
| else if (key.isReadable()) |
| doRead(key); |
| } |
| } catch (IOException e) { |
| } |
| key = null; |
| } |
| } catch (OutOfMemoryError e) { |
| // we can run out of memory if we have too many threads |
| // log the event and sleep for a minute and give |
| // some thread(s) a chance to finish |
| LOG.warn("Out of Memory in server select", e); |
| closeCurrentConnection(key, e); |
| cleanupConnections(true); |
| try { Thread.sleep(60000); } catch (Exception ie) {} |
| } catch (InterruptedException e) { |
| if (running) { // unexpected -- log it |
| LOG.info(getName() + " caught: " + |
| StringUtils.stringifyException(e)); |
| } |
| } catch (Exception e) { |
| closeCurrentConnection(key, e); |
| } |
| cleanupConnections(false); |
| } |
| LOG.info("Stopping " + this.getName()); |
| |
| synchronized (this) { |
| try { |
| acceptChannel.close(); |
| selector.close(); |
| } catch (IOException e) { } |
| |
| selector= null; |
| acceptChannel= null; |
| |
| // clean up all connections |
| while (!connectionList.isEmpty()) { |
| closeConnection(connectionList.remove(0)); |
| } |
| } |
| } |
| |
| private void closeCurrentConnection(SelectionKey key, Throwable e) { |
| if (key != null) { |
| Connection c = (Connection)key.attachment(); |
| if (c != null) { |
| if (LOG.isDebugEnabled()) |
| LOG.debug(getName() + ": disconnecting client " + c.getHostAddress()); |
| closeConnection(c); |
| c = null; |
| } |
| } |
| } |
| |
| InetSocketAddress getAddress() { |
| return (InetSocketAddress)acceptChannel.socket().getLocalSocketAddress(); |
| } |
| |
| void doAccept(SelectionKey key) throws IOException, OutOfMemoryError { |
| Connection c = null; |
| ServerSocketChannel server = (ServerSocketChannel) key.channel(); |
| // accept up to 10 connections |
| for (int i=0; i<10; i++) { |
| SocketChannel channel = server.accept(); |
| if (channel==null) return; |
| |
| channel.configureBlocking(false); |
| channel.socket().setTcpNoDelay(tcpNoDelay); |
| SelectionKey readKey = channel.register(getSelector(), |
| SelectionKey.OP_READ); |
| c = new Connection(readKey, channel, System.currentTimeMillis()); |
| readKey.attach(c); |
| synchronized (connectionList) { |
| connectionList.add(numConnections, c); |
| numConnections++; |
| } |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Server connection from " + c.toString() + |
| "; # active connections: " + numConnections + |
| "; # queued calls: " + callQueue.size()); |
| } |
| } |
| |
| void doRead(SelectionKey key) throws InterruptedException { |
| int count = 0; |
| Connection c = (Connection)key.attachment(); |
| if (c == null) { |
| return; |
| } |
| c.setLastContact(System.currentTimeMillis()); |
| |
| try { |
| count = c.readAndProcess(); |
| } catch (InterruptedException ieo) { |
| LOG.info(getName() + ": readAndProcess caught InterruptedException", ieo); |
| throw ieo; |
| } catch (Exception e) { |
| LOG.info(getName() + ": readAndProcess threw exception " + e + ". Count of bytes read: " + count, e); |
| count = -1; //so that the (count < 0) block is executed |
| } |
| if (count < 0) { |
| if (LOG.isDebugEnabled()) |
| LOG.debug(getName() + ": disconnecting client " + |
| c.getHostAddress() + ". Number of active connections: "+ |
| numConnections); |
| closeConnection(c); |
| c = null; |
| } |
| else { |
| c.setLastContact(System.currentTimeMillis()); |
| } |
| } |
| |
| synchronized void doStop() { |
| if (selector != null) { |
| selector.wakeup(); |
| Thread.yield(); |
| } |
| if (acceptChannel != null) { |
| try { |
| acceptChannel.socket().close(); |
| } catch (IOException e) { |
| LOG.info(getName() + ":Exception in closing listener socket. " + e); |
| } |
| } |
| } |
| |
| synchronized Selector getSelector() { return selector; } |
| } |
| |
| // Sends responses of RPC back to clients. |
| private class Responder extends Thread { |
| private Selector writeSelector; |
| private int pending; // connections waiting to register |
| |
| final static int PURGE_INTERVAL = 900000; // 15mins |
| |
| Responder() throws IOException { |
| this.setName("IPC Server Responder"); |
| this.setDaemon(true); |
| writeSelector = Selector.open(); // create a selector |
| pending = 0; |
| } |
| |
| @Override |
| public void run() { |
| LOG.info(getName() + ": starting"); |
| SERVER.set(Server.this); |
| long lastPurgeTime = 0; // last check for old calls. |
| |
| while (running) { |
| try { |
| waitPending(); // If a channel is being registered, wait. |
| writeSelector.select(PURGE_INTERVAL); |
| Iterator<SelectionKey> iter = writeSelector.selectedKeys().iterator(); |
| while (iter.hasNext()) { |
| SelectionKey key = iter.next(); |
| iter.remove(); |
| try { |
| if (key.isValid() && key.isWritable()) { |
| doAsyncWrite(key); |
| } |
| } catch (IOException e) { |
| LOG.info(getName() + ": doAsyncWrite threw exception " + e); |
| } |
| } |
| long now = System.currentTimeMillis(); |
| if (now < lastPurgeTime + PURGE_INTERVAL) { |
| continue; |
| } |
| lastPurgeTime = now; |
| // |
| // If there were some calls that have not been sent out for a |
| // long time, discard them. |
| // |
| LOG.debug("Checking for old call responses."); |
| ArrayList<Call> calls; |
| |
| // get the list of channels from list of keys. |
| synchronized (writeSelector.keys()) { |
| calls = new ArrayList<Call>(writeSelector.keys().size()); |
| iter = writeSelector.keys().iterator(); |
| while (iter.hasNext()) { |
| SelectionKey key = iter.next(); |
| Call call = (Call)key.attachment(); |
| if (call != null && key.channel() == call.connection.channel) { |
| calls.add(call); |
| } |
| } |
| } |
| |
| for(Call call : calls) { |
| try { |
| doPurge(call, now); |
| } catch (IOException e) { |
| LOG.warn("Error in purging old calls " + e); |
| } |
| } |
| } catch (OutOfMemoryError e) { |
| // |
| // we can run out of memory if we have too many threads |
| // log the event and sleep for a minute and give |
| // some thread(s) a chance to finish |
| // |
| LOG.warn("Out of Memory in server select", e); |
| try { Thread.sleep(60000); } catch (Exception ie) {} |
| } catch (Exception e) { |
| LOG.warn("Exception in Responder " + |
| StringUtils.stringifyException(e)); |
| } |
| } |
| LOG.info("Stopping " + this.getName()); |
| } |
| |
| private void doAsyncWrite(SelectionKey key) throws IOException { |
| Call call = (Call)key.attachment(); |
| if (call == null) { |
| return; |
| } |
| if (key.channel() != call.connection.channel) { |
| throw new IOException("doAsyncWrite: bad channel"); |
| } |
| |
| synchronized(call.connection.responseQueue) { |
| if (processResponse(call.connection.responseQueue, false)) { |
| try { |
| key.interestOps(0); |
| } catch (CancelledKeyException e) { |
| /* The Listener/reader might have closed the socket. |
| * We don't explicitly cancel the key, so not sure if this will |
| * ever fire. |
| * This warning could be removed. |
| */ |
| LOG.warn("Exception while changing ops : " + e); |
| } |
| } |
| } |
| } |
| |
| // |
| // Remove calls that have been pending in the responseQueue |
| // for a long time. |
| // |
| private void doPurge(Call call, long now) throws IOException { |
| LinkedList<Call> responseQueue = call.connection.responseQueue; |
| synchronized (responseQueue) { |
| Iterator<Call> iter = responseQueue.listIterator(0); |
| while (iter.hasNext()) { |
| call = iter.next(); |
| if (now > call.timestamp + PURGE_INTERVAL) { |
| closeConnection(call.connection); |
| break; |
| } |
| } |
| } |
| } |
| |
| // Processes one response. Returns true if there are no more pending |
| // data for this channel. |
| // |
| private boolean processResponse(LinkedList<Call> responseQueue, |
| boolean inHandler) throws IOException { |
| boolean error = true; |
| boolean done = false; // there is more data for this channel. |
| int numElements = 0; |
| Call call = null; |
| try { |
| synchronized (responseQueue) { |
| // |
| // If there are no items for this channel, then we are done |
| // |
| numElements = responseQueue.size(); |
| if (numElements == 0) { |
| error = false; |
| return true; // no more data for this channel. |
| } |
| // |
| // Extract the first call |
| // |
| call = responseQueue.removeFirst(); |
| SocketChannel channel = call.connection.channel; |
| if (LOG.isDebugEnabled()) { |
| LOG.debug(getName() + ": responding to #" + call.id + " from " + |
| call.connection); |
| } |
| // |
| // Send as much data as we can in the non-blocking fashion |
| // |
| int numBytes = channelWrite(channel, call.response); |
| if (numBytes < 0) { |
| return true; |
| } |
| if (!call.response.hasRemaining()) { |
| call.connection.decRpcCount(); |
| if (numElements == 1) { // last call fully processes. |
| done = true; // no more data for this channel. |
| } else { |
| done = false; // more calls pending to be sent. |
| } |
| if (LOG.isDebugEnabled()) { |
| LOG.debug(getName() + ": responding to #" + call.id + " from " + |
| call.connection + " Wrote " + numBytes + " bytes."); |
| } |
| } else { |
| // |
| // If we were unable to write the entire response out, then |
| // insert in Selector queue. |
| // |
| call.connection.responseQueue.addFirst(call); |
| |
| if (inHandler) { |
| // set the serve time when the response has to be sent later |
| call.timestamp = System.currentTimeMillis(); |
| |
| incPending(); |
| try { |
| // Wakeup the thread blocked on select, only then can the call |
| // to channel.register() complete. |
| writeSelector.wakeup(); |
| channel.register(writeSelector, SelectionKey.OP_WRITE, call); |
| } catch (ClosedChannelException e) { |
| //Its ok. channel might be closed else where. |
| done = true; |
| } finally { |
| decPending(); |
| } |
| } |
| if (LOG.isDebugEnabled()) { |
| LOG.debug(getName() + ": responding to #" + call.id + " from " + |
| call.connection + " Wrote partial " + numBytes + |
| " bytes."); |
| } |
| } |
| error = false; // everything went off well |
| } |
| } finally { |
| if (error && call != null) { |
| LOG.warn(getName()+", call " + call + ": output error"); |
| done = true; // error. no more data for this channel. |
| closeConnection(call.connection); |
| } |
| } |
| return done; |
| } |
| |
| // |
| // Enqueue a response from the application. |
| // |
| void doRespond(Call call) throws IOException { |
| synchronized (call.connection.responseQueue) { |
| call.connection.responseQueue.addLast(call); |
| if (call.connection.responseQueue.size() == 1) { |
| processResponse(call.connection.responseQueue, true); |
| } |
| } |
| } |
| |
| private synchronized void incPending() { // call waiting to be enqueued. |
| pending++; |
| } |
| |
| private synchronized void decPending() { // call done enqueueing. |
| pending--; |
| notify(); |
| } |
| |
| private synchronized void waitPending() throws InterruptedException { |
| while (pending > 0) { |
| wait(); |
| } |
| } |
| } |
| |
| /** Reads calls from a connection and queues them for handling. */ |
| private class Connection { |
| private boolean versionRead = false; //if initial signature and |
| //version are read |
| private boolean headerRead = false; //if the connection header that |
| //follows version is read. |
| |
| private SocketChannel channel; |
| private ByteBuffer data; |
| private ByteBuffer dataLengthBuffer; |
| private LinkedList<Call> responseQueue; |
| private volatile int rpcCount = 0; // number of outstanding rpcs |
| private long lastContact; |
| private int dataLength; |
| private Socket socket; |
| // Cache the remote host & port info so that even if the socket is |
| // disconnected, we can say where it used to connect to. |
| private String hostAddress; |
| private int remotePort; |
| |
| ConnectionHeader header = new ConnectionHeader(); |
| Class<?> protocol; |
| |
| Subject user = null; |
| |
| // Fake 'call' for failed authorization response |
| private static final int AUTHROIZATION_FAILED_CALLID = -1; |
| private final Call authFailedCall = |
| new Call(AUTHROIZATION_FAILED_CALLID, null, null); |
| private ByteArrayOutputStream authFailedResponse = new ByteArrayOutputStream(); |
| |
| public Connection(SelectionKey key, SocketChannel channel, |
| long lastContact) { |
| this.channel = channel; |
| this.lastContact = lastContact; |
| this.data = null; |
| this.dataLengthBuffer = ByteBuffer.allocate(4); |
| this.socket = channel.socket(); |
| InetAddress addr = socket.getInetAddress(); |
| if (addr == null) { |
| this.hostAddress = "*Unknown*"; |
| } else { |
| this.hostAddress = addr.getHostAddress(); |
| } |
| this.remotePort = socket.getPort(); |
| this.responseQueue = new LinkedList<Call>(); |
| if (socketSendBufferSize != 0) { |
| try { |
| socket.setSendBufferSize(socketSendBufferSize); |
| } catch (IOException e) { |
| LOG.warn("Connection: unable to set socket send buffer size to " + |
| socketSendBufferSize); |
| } |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return getHostAddress() + ":" + remotePort; |
| } |
| |
| public String getHostAddress() { |
| return hostAddress; |
| } |
| |
| public void setLastContact(long lastContact) { |
| this.lastContact = lastContact; |
| } |
| |
| public long getLastContact() { |
| return lastContact; |
| } |
| |
| /* Return true if the connection has no outstanding rpc */ |
| private boolean isIdle() { |
| return rpcCount == 0; |
| } |
| |
| /* Decrement the outstanding RPC count */ |
| private void decRpcCount() { |
| rpcCount--; |
| } |
| |
| /* Increment the outstanding RPC count */ |
| private void incRpcCount() { |
| rpcCount++; |
| } |
| |
| private boolean timedOut(long currentTime) { |
| if (isIdle() && currentTime - lastContact > maxIdleTime) |
| return true; |
| return false; |
| } |
| |
| public int readAndProcess() throws IOException, InterruptedException { |
| while (true) { |
| /* Read at most one RPC. If the header is not read completely yet |
| * then iterate until we read first RPC or until there is no data left. |
| */ |
| int count = -1; |
| if (dataLengthBuffer.remaining() > 0) { |
| count = channelRead(channel, dataLengthBuffer); |
| if (count < 0 || dataLengthBuffer.remaining() > 0) |
| return count; |
| } |
| |
| if (!versionRead) { |
| //Every connection is expected to send the header. |
| ByteBuffer versionBuffer = ByteBuffer.allocate(1); |
| count = channelRead(channel, versionBuffer); |
| if (count <= 0) { |
| return count; |
| } |
| int version = versionBuffer.get(0); |
| |
| dataLengthBuffer.flip(); |
| if (!HEADER.equals(dataLengthBuffer) || version != CURRENT_VERSION) { |
| //Warning is ok since this is not supposed to happen. |
| LOG.warn("Incorrect header or version mismatch from " + |
| hostAddress + ":" + remotePort + |
| " got version " + version + |
| " expected version " + CURRENT_VERSION); |
| return -1; |
| } |
| dataLengthBuffer.clear(); |
| versionRead = true; |
| continue; |
| } |
| |
| if (data == null) { |
| dataLengthBuffer.flip(); |
| dataLength = dataLengthBuffer.getInt(); |
| |
| if (dataLength == Client.PING_CALL_ID) { |
| dataLengthBuffer.clear(); |
| return 0; //ping message |
| } |
| data = ByteBuffer.allocate(dataLength); |
| incRpcCount(); // Increment the rpc count |
| } |
| |
| count = channelRead(channel, data); |
| |
| if (data.remaining() == 0) { |
| dataLengthBuffer.clear(); |
| data.flip(); |
| if (headerRead) { |
| processData(); |
| data = null; |
| return count; |
| } else { |
| processHeader(); |
| headerRead = true; |
| data = null; |
| |
| // Authorize the connection |
| try { |
| authorize(user, header); |
| |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Successfully authorized " + header); |
| } |
| } catch (AuthorizationException ae) { |
| authFailedCall.connection = this; |
| setupResponse(authFailedResponse, authFailedCall, |
| Status.FATAL, null, |
| ae.getClass().getName(), ae.getMessage()); |
| responder.doRespond(authFailedCall); |
| |
| // Close this connection |
| return -1; |
| } |
| |
| continue; |
| } |
| } |
| return count; |
| } |
| } |
| |
| /// Reads the connection header following version |
| private void processHeader() throws IOException { |
| DataInputStream in = |
| new DataInputStream(new ByteArrayInputStream(data.array())); |
| header.readFields(in); |
| try { |
| String protocolClassName = header.getProtocol(); |
| if (protocolClassName != null) { |
| protocol = getProtocolClass(header.getProtocol(), conf); |
| } |
| } catch (ClassNotFoundException cnfe) { |
| throw new IOException("Unknown protocol: " + header.getProtocol()); |
| } |
| |
| // TODO: Get the user name from the GSS API for Kerberbos-based security |
| // Create the user subject |
| user = SecurityUtil.getSubject(header.getUgi()); |
| } |
| |
| private void processData() throws IOException, InterruptedException { |
| DataInputStream dis = |
| new DataInputStream(new ByteArrayInputStream(data.array())); |
| int id = dis.readInt(); // try to read an id |
| |
| if (LOG.isDebugEnabled()) |
| LOG.debug(" got #" + id); |
| |
| Writable param = ReflectionUtils.newInstance(paramClass, conf); // read param |
| param.readFields(dis); |
| |
| Call call = new Call(id, param, this); |
| callQueue.put(call); // queue the call; maybe blocked here |
| } |
| |
| private synchronized void close() throws IOException { |
| data = null; |
| dataLengthBuffer = null; |
| if (!channel.isOpen()) |
| return; |
| try {socket.shutdownOutput();} catch(Exception e) { |
| LOG.warn("Ignoring socket shutdown exception"); |
| } |
| if (channel.isOpen()) { |
| try {channel.close();} catch(Exception e) {} |
| } |
| try {socket.close();} catch(Exception e) {} |
| } |
| } |
| |
| /** Handles queued calls . */ |
| private class Handler extends Thread { |
| public Handler(int instanceNumber) { |
| this.setDaemon(true); |
| this.setName("IPC Server handler "+ instanceNumber + " on " + port); |
| } |
| |
| @Override |
| public void run() { |
| LOG.info(getName() + ": starting"); |
| SERVER.set(Server.this); |
| ByteArrayOutputStream buf = |
| new ByteArrayOutputStream(INITIAL_RESP_BUF_SIZE); |
| while (running) { |
| try { |
| final Call call = callQueue.take(); // pop the queue; maybe blocked here |
| |
| if (LOG.isDebugEnabled()) |
| LOG.debug(getName() + ": has #" + call.id + " from " + |
| call.connection); |
| |
| String errorClass = null; |
| String error = null; |
| Writable value = null; |
| |
| CurCall.set(call); |
| try { |
| // Make the call as the user via Subject.doAs, thus associating |
| // the call with the Subject |
| value = |
| Subject.doAs(call.connection.user, |
| new PrivilegedExceptionAction<Writable>() { |
| @Override |
| public Writable run() throws Exception { |
| // make the call |
| return call(call.connection.protocol, |
| call.param, call.timestamp); |
| |
| } |
| } |
| ); |
| |
| } catch (PrivilegedActionException pae) { |
| Exception e = pae.getException(); |
| LOG.info(getName()+", call "+call+": error: " + e, e); |
| errorClass = e.getClass().getName(); |
| error = StringUtils.stringifyException(e); |
| } catch (Throwable e) { |
| LOG.info(getName()+", call "+call+": error: " + e, e); |
| errorClass = e.getClass().getName(); |
| error = StringUtils.stringifyException(e); |
| } |
| CurCall.set(null); |
| setupResponse(buf, call, |
| (error == null) ? Status.SUCCESS : Status.ERROR, |
| value, errorClass, error); |
| // Discard the large buf and reset it back to |
| // smaller size to freeup heap |
| if (buf.size() > MAX_RESP_BUF_SIZE) { |
| LOG.warn("Large response size " + buf.size() + " for call " + |
| call.toString()); |
| buf = new ByteArrayOutputStream(INITIAL_RESP_BUF_SIZE); |
| } |
| responder.doRespond(call); |
| } catch (InterruptedException e) { |
| if (running) { // unexpected -- log it |
| LOG.info(getName() + " caught: " + |
| StringUtils.stringifyException(e)); |
| } |
| } catch (Exception e) { |
| LOG.info(getName() + " caught: " + |
| StringUtils.stringifyException(e)); |
| } |
| } |
| LOG.info(getName() + ": exiting"); |
| } |
| |
| } |
| |
| protected Server(String bindAddress, int port, |
| Class<? extends Writable> paramClass, int handlerCount, |
| Configuration conf) |
| throws IOException |
| { |
| this(bindAddress, port, paramClass, handlerCount, conf, Integer.toString(port)); |
| } |
| /** Constructs a server listening on the named port and address. Parameters passed must |
| * be of the named class. The <code>handlerCount</handlerCount> determines |
| * the number of handler threads that will be used to process calls. |
| * |
| */ |
| protected Server(String bindAddress, int port, |
| Class<? extends Writable> paramClass, int handlerCount, |
| Configuration conf, String serverName) |
| throws IOException { |
| this.bindAddress = bindAddress; |
| this.conf = conf; |
| this.port = port; |
| this.paramClass = paramClass; |
| this.handlerCount = handlerCount; |
| this.socketSendBufferSize = 0; |
| this.maxQueueSize = handlerCount * conf.getInt( |
| CommonConfigurationKeys.IPC_SERVER_HANDLER_QUEUE_SIZE_KEY, |
| CommonConfigurationKeys.IPC_SERVER_HANDLER_QUEUE_SIZE_DEFAULT); |
| this.callQueue = new LinkedBlockingQueue<Call>(maxQueueSize); |
| this.maxIdleTime = 2*conf.getInt("ipc.client.connection.maxidletime", 1000); |
| this.maxConnectionsToNuke = conf.getInt("ipc.client.kill.max", 10); |
| this.thresholdIdleConnections = conf.getInt("ipc.client.idlethreshold", 4000); |
| |
| // Start the listener here and let it bind to the port |
| listener = new Listener(); |
| this.port = listener.getAddress().getPort(); |
| this.rpcMetrics = new RpcMetrics(serverName, |
| Integer.toString(this.port), this); |
| this.tcpNoDelay = conf.getBoolean("ipc.server.tcpnodelay", false); |
| |
| |
| // Create the responder here |
| responder = new Responder(); |
| } |
| |
| private void closeConnection(Connection connection) { |
| synchronized (connectionList) { |
| if (connectionList.remove(connection)) |
| numConnections--; |
| } |
| try { |
| connection.close(); |
| } catch (IOException e) { |
| } |
| } |
| |
| /** |
| * Setup response for the IPC Call. |
| * |
| * @param response buffer to serialize the response into |
| * @param call {@link Call} to which we are setting up the response |
| * @param status {@link Status} of the IPC call |
| * @param rv return value for the IPC Call, if the call was successful |
| * @param errorClass error class, if the the call failed |
| * @param error error message, if the call failed |
| * @throws IOException |
| */ |
| private void setupResponse(ByteArrayOutputStream response, |
| Call call, Status status, |
| Writable rv, String errorClass, String error) |
| throws IOException { |
| response.reset(); |
| DataOutputStream out = new DataOutputStream(response); |
| out.writeInt(call.id); // write call id |
| out.writeInt(status.state); // write status |
| |
| if (status == Status.SUCCESS) { |
| rv.write(out); |
| } else { |
| WritableUtils.writeString(out, errorClass); |
| WritableUtils.writeString(out, error); |
| } |
| call.setResponse(ByteBuffer.wrap(response.toByteArray())); |
| } |
| |
| Configuration getConf() { |
| return conf; |
| } |
| |
| /** Sets the socket buffer size used for responding to RPCs */ |
| public void setSocketSendBufSize(int size) { this.socketSendBufferSize = size; } |
| |
| /** Starts the service. Must be called before any calls will be handled. */ |
| public synchronized void start() throws IOException { |
| responder.start(); |
| listener.start(); |
| handlers = new Handler[handlerCount]; |
| |
| for (int i = 0; i < handlerCount; i++) { |
| handlers[i] = new Handler(i); |
| handlers[i].start(); |
| } |
| } |
| |
| /** Stops the service. No new calls will be handled after this is called. */ |
| public synchronized void stop() { |
| LOG.info("Stopping server on " + port); |
| running = false; |
| if (handlers != null) { |
| for (int i = 0; i < handlerCount; i++) { |
| if (handlers[i] != null) { |
| handlers[i].interrupt(); |
| } |
| } |
| } |
| listener.interrupt(); |
| listener.doStop(); |
| responder.interrupt(); |
| notifyAll(); |
| if (this.rpcMetrics != null) { |
| this.rpcMetrics.shutdown(); |
| } |
| } |
| |
| /** Wait for the server to be stopped. |
| * Does not wait for all subthreads to finish. |
| * See {@link #stop()}. |
| */ |
| public synchronized void join() throws InterruptedException { |
| while (running) { |
| wait(); |
| } |
| } |
| |
| /** |
| * Return the socket (ip+port) on which the RPC server is listening to. |
| * @return the socket (ip+port) on which the RPC server is listening to. |
| */ |
| public synchronized InetSocketAddress getListenerAddress() { |
| return listener.getAddress(); |
| } |
| |
| /** |
| * Called for each call. |
| * @deprecated Use {@link #call(Class, Writable, long)} instead |
| */ |
| @Deprecated |
| public Writable call(Writable param, long receiveTime) throws IOException { |
| return call(null, param, receiveTime); |
| } |
| |
| /** Called for each call. */ |
| public abstract Writable call(Class<?> protocol, |
| Writable param, long receiveTime) |
| throws IOException; |
| |
| /** |
| * Authorize the incoming client connection. |
| * |
| * @param user client user |
| * @param connection incoming connection |
| * @throws AuthorizationException when the client isn't authorized to talk the protocol |
| */ |
| public void authorize(Subject user, ConnectionHeader connection) |
| throws AuthorizationException {} |
| |
| /** |
| * The number of open RPC conections |
| * @return the number of open rpc connections |
| */ |
| public int getNumOpenConnections() { |
| return numConnections; |
| } |
| |
| /** |
| * The number of rpc calls in the queue. |
| * @return The number of rpc calls in the queue. |
| */ |
| public int getCallQueueLen() { |
| return callQueue.size(); |
| } |
| |
| |
| /** |
| * When the read or write buffer size is larger than this limit, i/o will be |
| * done in chunks of this size. Most RPC requests and responses would be |
| * be smaller. |
| */ |
| private static int NIO_BUFFER_LIMIT = 8*1024; //should not be more than 64KB. |
| |
| /** |
| * This is a wrapper around {@link WritableByteChannel#write(ByteBuffer)}. |
| * If the amount of data is large, it writes to channel in smaller chunks. |
| * This is to avoid jdk from creating many direct buffers as the size of |
| * buffer increases. This also minimizes extra copies in NIO layer |
| * as a result of multiple write operations required to write a large |
| * buffer. |
| * |
| * @see WritableByteChannel#write(ByteBuffer) |
| */ |
| private static int channelWrite(WritableByteChannel channel, |
| ByteBuffer buffer) throws IOException { |
| |
| return (buffer.remaining() <= NIO_BUFFER_LIMIT) ? |
| channel.write(buffer) : channelIO(null, channel, buffer); |
| } |
| |
| |
| /** |
| * This is a wrapper around {@link ReadableByteChannel#read(ByteBuffer)}. |
| * If the amount of data is large, it writes to channel in smaller chunks. |
| * This is to avoid jdk from creating many direct buffers as the size of |
| * ByteBuffer increases. There should not be any performance degredation. |
| * |
| * @see ReadableByteChannel#read(ByteBuffer) |
| */ |
| private static int channelRead(ReadableByteChannel channel, |
| ByteBuffer buffer) throws IOException { |
| |
| return (buffer.remaining() <= NIO_BUFFER_LIMIT) ? |
| channel.read(buffer) : channelIO(channel, null, buffer); |
| } |
| |
| /** |
| * Helper for {@link #channelRead(ReadableByteChannel, ByteBuffer)} |
| * and {@link #channelWrite(WritableByteChannel, ByteBuffer)}. Only |
| * one of readCh or writeCh should be non-null. |
| * |
| * @see #channelRead(ReadableByteChannel, ByteBuffer) |
| * @see #channelWrite(WritableByteChannel, ByteBuffer) |
| */ |
| private static int channelIO(ReadableByteChannel readCh, |
| WritableByteChannel writeCh, |
| ByteBuffer buf) throws IOException { |
| |
| int originalLimit = buf.limit(); |
| int initialRemaining = buf.remaining(); |
| int ret = 0; |
| |
| while (buf.remaining() > 0) { |
| try { |
| int ioSize = Math.min(buf.remaining(), NIO_BUFFER_LIMIT); |
| buf.limit(buf.position() + ioSize); |
| |
| ret = (readCh == null) ? writeCh.write(buf) : readCh.read(buf); |
| |
| if (ret < ioSize) { |
| break; |
| } |
| |
| } finally { |
| buf.limit(originalLimit); |
| } |
| } |
| |
| int nBytes = initialRemaining - buf.remaining(); |
| return (nBytes > 0) ? nBytes : ret; |
| } |
| } |
