LogFileManager xref

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    1   /***
    2    *
    3    * Copyright 2004 Hiram Chirino
    4    *
    5    * Licensed under the Apache License, Version 2.0 (the "License");
    6    * you may not use this file except in compliance with the License.
    7    * You may obtain a copy of the License at
    8    *
    9    * http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   **/
    18  package org.codehaus.activemq.journal.impl;
    19
    20  import java.io.File;
    21  import java.io.IOException;
    22  import java.io.InterruptedIOException;
    23  import java.lang.reflect.InvocationTargetException;
    24
    25  import org.apache.commons.logging.Log;
    26  import org.apache.commons.logging.LogFactory;
    27  import org.codehaus.activemq.journal.InvalidRecordLocationException;
    28  import org.codehaus.activemq.journal.JournalEventListener;
    29  import org.codehaus.activemq.util.LongSequenceGenerator;
    30
    31  import EDU.oswego.cs.dl.util.concurrent.FutureResult;
    32  import EDU.oswego.cs.dl.util.concurrent.QueuedExecutor;
    33  import EDU.oswego.cs.dl.util.concurrent.ThreadFactory;
    34
    35  /***
    36   * The LogFileManager manages concurent access to a LogFile.
    37   *
    38   * @version $Revision: 1.7 $
    39   */
    40  public class LogFileManager {
    41
    42      static final private Log log = LogFactory.getLog(LogFileManager.class);
    43
    44      static final private int LOG_HEADER_SIZE=512;
    45      static final private int OVERFLOW_RENOTIFICATION_DELAY=500;
    46
    47  	private final LongSequenceGenerator sequenceGenerator;
    48  	private final byte fileManagerId;
    49  	private boolean closed=false;
    50
    51  	// The id of the file that has the mark.
    52  	private byte markedSegmentIndex=0;
    53  	// The id of the current log file that is being filled.
    54  	private byte appendSegmentIndex=0;
    55  	// The offset in the current log file that is being filled.
    56  	private int appendSegmentOffset=0;
    57
    58  	// Used to batch writes together.
    59  	private BatchedWrite pendingBatchWrite;
    60
    61  	private RecordLocationImpl lastMarkedLocation;
    62      private LogFile file;
    63      private QueuedExecutor executor;
    64
    65      private int rolloverFence;
    66      private JournalEventListener eventListener;
    67  	private ByteBufferPool byteBufferPool;
    68
    69  	private long overflowNotificationTime=System.currentTimeMillis();
    70
    71  	/***
    72  	 */
    73  	public LogFileManager(byte fileManagerId, LongSequenceGenerator sequenceGenerator, File logDirectory)
    74  		throws IOException {
    75  	    this( fileManagerId, sequenceGenerator, new LogFile(logDirectory) );
    76  	}
    77
    78  	/***
    79  	 */
    80  	public LogFileManager(byte fileManagerId, LongSequenceGenerator sequenceGenerator, LogFile logFile) {
    81  		this.fileManagerId = fileManagerId;
    82  		this.sequenceGenerator = sequenceGenerator;
    83  	    this.file = logFile;
    84  	    this.byteBufferPool = new ByteBufferPool();
    85  		this.executor = new QueuedExecutor();
    86  		this.executor.setThreadFactory(new ThreadFactory(){
    87  			public Thread newThread(Runnable runnable) {
    88  				Thread answer = new Thread(runnable, "Journal Writter");
    89  				answer.setPriority(Thread.MAX_PRIORITY);
    90  				answer.setDaemon(true);
    91  				return answer;
    92  			}
    93  		});
    94
    95
    96  		lastMarkedLocation = file.getLastMarkedRecordLocation(fileManagerId);
    97  		appendSegmentIndex = file.getAppendSegmentIndex();
    98  		appendSegmentOffset = file.getAppendSegmentOffset();
    99  		rolloverFence = (file.getInitialSegmentSize()/10)*9;
    100 	}
    101
    102 	public RecordLocationImpl write(byte[] data, boolean sync) throws IOException {
    103 	    return write(LogFile.DATA_RECORD_TYPE, data, sync, null);
    104 	}
    105
    106 	private RecordLocationImpl write(byte recordType, byte[] data, boolean sync, Mark mark) throws IOException {
    107 		try {
    108 			RecordLocationImpl location;
    109 			BatchedWrite writeCommand;
    110 			synchronized( this ) {
    111 				if(closed) {
    112 					throw new IOException("Journal has been closed.");
    113 				}
    114
    115 				// Create our record
    116 				long sequenceId = sequenceGenerator.getNextSequenceId();
    117 				location = new RecordLocationImpl(this.fileManagerId, appendSegmentIndex, appendSegmentOffset, sequenceId);
    118 				Record record = new Record(sequenceId, recordType, data, mark );
    119 				// Piggy back the packet on the pending write batch.
    120 				writeCommand = addToPendingWriteBatch(record);
    121
    122 				// Update where the next record will land.
    123 				appendSegmentOffset += data.length+Record.RECORD_BASE_SIZE;
    124 				rolloverCheck();
    125 			}
    126
    127 			if( sync ) {
    128 				writeCommand.waitForForce();
    129 			}
    130
    131 			return location;
    132 		} catch (IOException e) {
    133 			throw e;
    134 		} catch (InterruptedException e) {
    135 			throw (IOException)new InterruptedIOException().initCause(e);
    136 		} catch (Throwable e) {
    137 			throw (IOException)new IOException("Write failed: "+e).initCause(e);
    138 		}
    139 	}
    140
    141     /***
    142 	 * @param record
    143 	 * @return
    144 	 * @throws InterruptedException
    145 	 */
    146 	private BatchedWrite addToPendingWriteBatch(Record record) throws InterruptedException {
    147
    148 		// Load the write batch up with data from our record.
    149 		// it may take more than one write batch if the record is large.
    150 	    BatchedWrite answer=null;
    151 		while( record.remaining()>0 ) {
    152 			// Do we need another BatchWrite?
    153 			if( pendingBatchWrite==null ) {
    154 				final BatchedWrite write = new BatchedWrite(byteBufferPool.getByteBuffer());
    155 				pendingBatchWrite = write;
    156 				executor.execute(new Runnable() {
    157                     public void run() {
    158                         try {
    159                             queuedWrite(write);
    160                         } catch (InterruptedException e) {
    161                         }
    162                     }
    163 				});
    164 			}
    165 			answer = pendingBatchWrite;
    166 			// Can we continue to use the pendingBatchWrite?
    167 			if( !pendingBatchWrite.append(record) ) {
    168 			    pendingBatchWrite = null;
    169 			}
    170 		}
    171 		return answer;
    172
    173 	}
    174
    175 	/***
    176 	 * This is a blocking call
    177 	 * @param write
    178 	 * @throws InterruptedException
    179 	 */
    180 	private void queuedWrite(BatchedWrite write) throws InterruptedException {
    181
    182 	    // Stop other threads from appending more pendingBatchWrite.
    183 		write.disableAppend();
    184
    185 		// Do the write.
    186 		try {
    187 			file.appendAndForce(write);
    188 			write.forced();
    189 		} catch (Throwable e) {
    190 		    write.writeFailed(e);
    191 		} finally {
    192 			byteBufferPool.returnByteBuffer(write.getByteBuffer());
    193 		}
    194 	}
    195
    196 	/***
    197      *
    198      */
    199     private void rolloverCheck() throws IOException {
    200
    201 		// See if we need to issue an overflow notification.
    202         if( eventListener!=null
    203         		&& !file.canActivateNextSegment()
    204 				&& overflowNotificationTime+OVERFLOW_RENOTIFICATION_DELAY < System.currentTimeMillis() ) {
    205
    206     		// We need to send an overflow notification to at free up
    207             // some segments.
    208         	RecordLocationImpl safeSpot = file.getFirstRecordLocationOfSecondActiveSegment(fileManagerId);
    209             eventListener.overflowNotification(safeSpot);
    210 			overflowNotificationTime = System.currentTimeMillis();
    211         }
    212
    213     	// Is it time to rollover and can we rollover?
    214         if( appendSegmentOffset > rolloverFence && file.canActivateNextSegment() ) {
    215
    216         	// don't delay the next overflow notification.
    217         	overflowNotificationTime -= OVERFLOW_RENOTIFICATION_DELAY;
    218
    219     	    final FutureResult result = new FutureResult();
    220     	    try {
    221     	        executor.execute(new Runnable() {
    222     	            public void run() {
    223     	                try {
    224     	                    result.set( queuedActivateNextSegment() );
    225     	                } catch (Throwable e) {
    226     	                    result.setException(e);
    227     	                }
    228     	            }
    229     		    });
    230                 appendSegmentIndex = ((Byte)result.get()).byteValue();
    231                 appendSegmentOffset = Segment.SEGMENT_HEADER_SIZE;
    232
    233             } catch (InterruptedException e) {
    234                 throw (IOException)new IOException("Interrupted.").initCause(e);
    235             } catch (InvocationTargetException e) {
    236                 if( e.getTargetException() instanceof IOException)
    237                     throw (IOException)new IOException(e.getTargetException().getMessage()).initCause(e.getTargetException());
    238                 throw (IOException)new IOException("Unexpected Exception: ").initCause(e.getTargetException());
    239             }
    240         }
    241     }
    242
    243     /***
    244 	 * This is a blocking call
    245 	 */
    246 	private Byte queuedActivateNextSegment() throws IOException {
    247 		file.activateNextSegment();
    248 	    return new Byte(file.getAppendSegmentIndex());
    249 	}
    250
    251
    252 	/***
    253 	 * @param recordLocator
    254 	 * @param force
    255 	 * @return
    256 	 * @throws InvalidRecordLocationException
    257 	 * @throws IOException
    258 	 * @throws InterruptedException
    259 	 */
    260 	synchronized public void setMark(final RecordLocationImpl recordLocator, boolean force) throws InvalidRecordLocationException, InterruptedException, IOException {
    261 		if( recordLocator==null )
    262 	        throw new InvalidRecordLocationException("The location cannot be null.");
    263 	    if( lastMarkedLocation!=null && recordLocator.compareTo(lastMarkedLocation)<0 )
    264 	        throw new InvalidRecordLocationException("The location is less than the last mark.");
    265 	    lastMarkedLocation = recordLocator;
    266 	    Mark mark = new Mark(recordLocator);
    267 	    byte data[] = mark.writeExternal();
    268 	    write(LogFile.MARK_RECORD_TYPE,data,force,mark);
    269 	}
    270
    271 	/***
    272 	 * @return
    273 	 */
    274 	public RecordLocationImpl getMark() {
    275 	    return lastMarkedLocation;
    276 	}
    277
    278 	/***
    279 	 * @param lastLocation
    280 	 * @return
    281 	 * @throws IOException
    282 	 * @throws InvalidRecordLocationException
    283 	 */
    284 	public RecordLocationImpl getNextRecordLocation(final RecordLocationImpl lastLocation) throws IOException, InvalidRecordLocationException {
    285 		if( lastLocation==null ) {
    286 			if( lastMarkedLocation!=null) {
    287 				return lastMarkedLocation;
    288 			} else {
    289                 byte safeSeg = file.getFirstActiveSegmentIndex();
    290 				try {
    291 					return file.readRecordLocation( new RecordLocationImpl(fileManagerId, safeSeg, Segment.SEGMENT_HEADER_SIZE));
    292 				} catch (InvalidRecordLocationException e1) {
    293 					return null;
    294 				}
    295 			}
    296 		}
    297
    298 	    // Run this in the queued executor thread.
    299 	    final FutureResult result = new FutureResult();
    300 	    try {
    301 	        executor.execute(new Runnable() {
    302 	            public void run() {
    303 	                try {
    304 	                    result.set( queuedGetNextRecordLocation(lastLocation) );
    305 	                } catch (Throwable e) {
    306 	                    result.setException(e);
    307 	                }
    308 	            }
    309 		    });
    310             return (RecordLocationImpl)result.get();
    311         } catch (InterruptedException e) {
    312             throw (IOException)new IOException("Interrupted.").initCause(e);
    313         } catch (InvocationTargetException e) {
    314             if( e.getTargetException() instanceof InvalidRecordLocationException)
    315                 throw new InvalidRecordLocationException(e.getTargetException().getMessage(),e.getTargetException());
    316             if( e.getTargetException() instanceof IOException)
    317                 throw (IOException)new IOException(e.getTargetException().getMessage()).initCause(e.getTargetException());
    318             throw (IOException)new IOException("Unexpected Exception: ").initCause(e.getTargetException());
    319         }
    320 	}
    321
    322 	private RecordLocationImpl queuedGetNextRecordLocation(RecordLocationImpl location) throws IOException, InvalidRecordLocationException {
    323 		return file.getNextDataRecordLocation(location);
    324 	}
    325
    326 	/***
    327 	 * @param location
    328 	 * @return
    329 	 * @throws InvalidRecordLocationException
    330 	 * @throws IOException
    331 	 */
    332 	public byte[] read(final RecordLocationImpl location) throws IOException, InvalidRecordLocationException {
    333 	    // Run this in the queued executor thread.
    334 	    final FutureResult result = new FutureResult();
    335 	    try {
    336 	        executor.execute(new Runnable() {
    337 	            public void run() {
    338 	                try {
    339 	                    result.set( queuedRead(location) );
    340 	                } catch (Throwable e) {
    341 	                    result.setException(e);
    342 	                }
    343 	            }
    344 		    });
    345             return (byte[])result.get();
    346         } catch (InterruptedException e) {
    347             throw (IOException)new IOException("Interrupted.").initCause(e);
    348         } catch (InvocationTargetException e) {
    349             if( e.getTargetException() instanceof InvalidRecordLocationException)
    350                 throw new InvalidRecordLocationException(e.getTargetException().getMessage(),e.getTargetException());
    351             if( e.getTargetException() instanceof IOException)
    352                 throw (IOException)new IOException(e.getTargetException().getMessage()).initCause(e.getTargetException());
    353             throw (IOException)new IOException("Unexpected Exception: ").initCause(e.getTargetException());
    354         }
    355 	}
    356
    357     private byte[] queuedRead(RecordLocationImpl newLocation) throws IOException, InvalidRecordLocationException {
    358
    359 	    int segmentIndex;
    360 	    int segmentOffset;
    361 	    if( newLocation==null ) {
    362 	        segmentIndex=markedSegmentIndex;
    363 	    	segmentOffset=Segment.SEGMENT_HEADER_SIZE;
    364 		} else {
    365 	        segmentIndex=newLocation.getSegmentIndex();
    366 	    	segmentOffset=newLocation.getSegmentOffset();
    367 		}
    368
    369 		return file.readData(segmentIndex,segmentOffset);
    370 	}
    371
    372     /***
    373      * @param eventListener
    374      */
    375     public void setJournalEventListener(JournalEventListener eventListener) {
    376         this.eventListener = eventListener;
    377     }
    378
    379 	/***
    380 	 * @throws InterruptedException
    381 	 *
    382 	 */
    383 	public void close() {
    384 		if(closed)
    385 			return;
    386 		executor.shutdownAfterProcessingCurrentlyQueuedTasks();
    387 	    try { file.close(); } catch ( Throwable e ) {}
    388 		closed = true;
    389 	}
    390
    391 	public long getLastSequenceId() {
    392 		return file.getLastSequenceId();
    393 	}
    394
    395 	/***
    396 	 * @return
    397 	 */
    398 	public File getLogDirectory() {
    399 		return file.getLogDirectory();
    400 	}
    401
    402 	public int getTotalSegements() {
    403 		return file.getTotalSegements();
    404 	}
    405
    406 	public int getInitialSegmentSize() {
    407 		return file.getInitialSegmentSize();
    408 	}
    409 }