org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/trace/indexer/checkpoint/TmfCheckpointIndexer.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012, 2013 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Francois Chouinard - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.core.trace.indexer.checkpoint;
  14
  15 import org.eclipse.core.runtime.IProgressMonitor;
  16 import org.eclipse.core.runtime.IStatus;
  17 import org.eclipse.core.runtime.Status;
  18 import org.eclipse.core.runtime.jobs.Job;
  19 import org.eclipse.linuxtools.internal.tmf.core.Messages;
  20 import org.eclipse.linuxtools.internal.tmf.core.trace.indexer.TmfMemoryIndex;
  21 import org.eclipse.linuxtools.tmf.core.component.TmfDataProvider;
  22 import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
  23 import org.eclipse.linuxtools.tmf.core.request.ITmfDataRequest;
  24 import org.eclipse.linuxtools.tmf.core.request.ITmfEventRequest;
  25 import org.eclipse.linuxtools.tmf.core.request.TmfDataRequest;
  26 import org.eclipse.linuxtools.tmf.core.request.TmfEventRequest;
  27 import org.eclipse.linuxtools.tmf.core.signal.TmfTraceUpdatedSignal;
  28 import org.eclipse.linuxtools.tmf.core.timestamp.ITmfTimestamp;
  29 import org.eclipse.linuxtools.tmf.core.timestamp.TmfTimeRange;
  30 import org.eclipse.linuxtools.tmf.core.trace.ITmfContext;
  31 import org.eclipse.linuxtools.tmf.core.trace.ITmfTrace;
  32 import org.eclipse.linuxtools.tmf.core.trace.indexer.ITmfTraceIndexer;
  33 import org.eclipse.linuxtools.tmf.core.trace.location.ITmfLocation;
  34
  35 /**
  36  * A simple indexer that manages the trace index as an array of trace
  37  * checkpoints. Checkpoints are stored in memory at fixed intervals (event rank) in
  38  * ascending timestamp order.
  39  * <p>
  40  * The goal being to access a random trace event reasonably fast from the user's
  41  * standpoint, picking the right interval value becomes a trade-off between speed
  42  * and memory usage (a shorter inter-event interval is faster but requires more
  43  * checkpoints).
  44  * <p>
  45  * Locating a specific checkpoint is trivial for both rank (rank % interval) and
  46  * timestamp (bsearch in the array).
  47  * *
  48  * @see ITmfTrace
  49  * @see ITmfEvent
  50  *
  51  * @author Francois Chouinard
  52  * @since 3.0
  53  */
  54 public class TmfCheckpointIndexer implements ITmfTraceIndexer {
  55
  56     // ------------------------------------------------------------------------
  57     // Attributes
  58     // ------------------------------------------------------------------------
  59
  60     /** The event trace to index */
  61     protected final ITmfTrace fTrace;
  62
  63     /** The interval between checkpoints */
  64     private final int fCheckpointInterval;
  65
  66     /** The event trace to index */
  67     private boolean fIsIndexing;
  68
  69     /**
  70      * The trace index. It is composed of checkpoints taken at intervals of
  71      * fCheckpointInterval events.
  72      */
  73     protected final ITmfCheckpointIndex fTraceIndex;
  74
  75     /**
  76      * The indexing request
  77      */
  78     private ITmfEventRequest fIndexingRequest = null;
  79
  80     // ------------------------------------------------------------------------
  81     // Construction
  82     // ------------------------------------------------------------------------
  83
  84     /**
  85      * Basic constructor that uses the default trace block size as checkpoints
  86      * intervals
  87      *
  88      * @param trace the trace to index
  89      */
  90     public TmfCheckpointIndexer(final ITmfTrace trace) {
  91         this(trace, TmfDataProvider.DEFAULT_BLOCK_SIZE);
  92     }
  93
  94     /**
  95      * Full trace indexer
  96      *
  97      * @param trace the trace to index
  98      * @param interval the checkpoints interval
  99      */
 100     public TmfCheckpointIndexer(final ITmfTrace trace, final int interval) {
 101         fTrace = trace;
 102         fCheckpointInterval = interval;
 103         fTraceIndex = createIndex(trace);
 104         fIsIndexing = false;
 105     }
 106
 107     /**
 108      * Creates the index instance. Classes extending this class
 109      * can override this to provide a different index implementation.
 110      *
 111      * @param trace the trace to index
 112      * @return the index
 113      * @since 3.0
 114      */
 115     protected ITmfCheckpointIndex createIndex(final ITmfTrace trace) {
 116         return new TmfMemoryIndex(trace);
 117     }
 118
 119     @Override
 120     public void dispose() {
 121         if ((fIndexingRequest != null) && !fIndexingRequest.isCompleted()) {
 122             fIndexingRequest.cancel();
 123         }
 124
 125         fTraceIndex.dispose();
 126     }
 127
 128     // ------------------------------------------------------------------------
 129     // ITmfTraceIndexer - isIndexing
 130     // ------------------------------------------------------------------------
 131
 132     @Override
 133     public boolean isIndexing() {
 134         return fIsIndexing;
 135     }
 136
 137     // ------------------------------------------------------------------------
 138     // ITmfTraceIndexer - buildIndex
 139     // ------------------------------------------------------------------------
 140
 141     /**
 142      * @since 2.0
 143      */
 144     @Override
 145     public void buildIndex(final long offset, final TmfTimeRange range, final boolean waitForCompletion) {
 146
 147         // Don't do anything if we are already indexing
 148         synchronized (fTraceIndex) {
 149             if (fIsIndexing) {
 150                 return;
 151             }
 152             fIsIndexing = true;
 153         }
 154
 155         // No need to build the index, it has been restored
 156         if (!fTraceIndex.isCreatedFromScratch()) {
 157             // Set some trace attributes that depends on indexing
 158             fTrace.broadcast(new TmfTraceUpdatedSignal(this, fTrace, new TmfTimeRange(fTraceIndex.getTimeRange().getStartTime(), fTraceIndex.getTimeRange().getEndTime()), fTraceIndex.getNbEvents()));
 159             return;
 160         }
 161
 162         // The monitoring job
 163         final Job job = new Job("Indexing " + fTrace.getName() + "...") { //$NON-NLS-1$ //$NON-NLS-2$
 164             @Override
 165             protected IStatus run(final IProgressMonitor monitor) {
 166                 monitor.beginTask("", IProgressMonitor.UNKNOWN); //$NON-NLS-1$
 167                 while (!monitor.isCanceled()) {
 168                     try {
 169                         long prevNbEvents = fTrace.getNbEvents();
 170                         Thread.sleep(250);
 171                         long nbEvents = fTrace.getNbEvents();
 172                         setName(Messages.TmfCheckpointIndexer_Indexing + ' ' + fTrace.getName() + " (" + nbEvents + ")"); //$NON-NLS-1$ //$NON-NLS-2$
 173                         // setName doesn't refresh the UI, setTaskName does
 174                         long rate = (nbEvents - prevNbEvents) * 4;
 175                         monitor.setTaskName(rate + " " + Messages.TmfCheckpointIndexer_EventsPerSecond); //$NON-NLS-1$
 176                     } catch (final InterruptedException e) {
 177                         return Status.OK_STATUS;
 178                     }
 179                 }
 180                 monitor.done();
 181                 return Status.OK_STATUS;
 182             }
 183         };
 184         job.schedule();
 185
 186         // Build a background request for all the trace data. The index is
 187         // updated as we go by readNextEvent().
 188         fIndexingRequest = new TmfEventRequest(ITmfEvent.class,
 189                 range, offset, TmfDataRequest.ALL_DATA,
 190                 ITmfDataRequest.ExecutionType.BACKGROUND) {
 191             @Override
 192             public void handleData(final ITmfEvent event) {
 193                 super.handleData(event);
 194                 if (event != null) {
 195                     // Update the trace status at regular intervals
 196                     if ((getNbRead() % fCheckpointInterval) == 0) {
 197                         updateTraceStatus();
 198                     }
 199                 }
 200             }
 201
 202             @Override
 203             public void handleSuccess() {
 204                 fTraceIndex.setTimeRange(fTrace.getTimeRange());
 205                 fTraceIndex.setNbEvents(fTrace.getNbEvents());
 206                 fTraceIndex.setIndexComplete();
 207                 updateTraceStatus();
 208             }
 209
 210             @Override
 211             public void handleCompleted() {
 212                 job.cancel();
 213                 super.handleCompleted();
 214                 fIsIndexing = false;
 215             }
 216
 217             private void updateTraceStatus() {
 218                 if (fTrace.getNbEvents() > 0) {
 219                     signalNewTimeRange(fTrace.getStartTime(), fTrace.getEndTime());
 220                 }
 221             }
 222         };
 223
 224         // Submit the request and wait for completion if required
 225         fTrace.sendRequest(fIndexingRequest);
 226         if (waitForCompletion) {
 227             try {
 228                 fIndexingRequest.waitForCompletion();
 229             } catch (final InterruptedException e) {
 230             }
 231         }
 232     }
 233
 234     /**
 235      * Notify the interested parties that the trace time range has changed
 236      *
 237      * @param startTime the new start time
 238      * @param endTime the new end time
 239      */
 240     private void signalNewTimeRange(final ITmfTimestamp startTime, final ITmfTimestamp endTime) {
 241         fTrace.broadcast(new TmfTraceUpdatedSignal(fTrace, fTrace, new TmfTimeRange(startTime, endTime), fTrace.getNbEvents()));
 242     }
 243
 244     // ------------------------------------------------------------------------
 245     // ITmfTraceIndexer - updateIndex
 246     // ------------------------------------------------------------------------
 247
 248     /**
 249      * @since 2.0
 250      */
 251     @Override
 252     public synchronized void updateIndex(final ITmfContext context, final ITmfTimestamp timestamp) {
 253         if ((context.getRank() % fCheckpointInterval) == 0) {
 254             // Determine the table position
 255             final long position = context.getRank() / fCheckpointInterval;
 256             // Add new entry at proper location (if empty)
 257             if (fTraceIndex.size() == position) {
 258                 fTraceIndex.insert(new TmfCheckpoint(timestamp, context.getLocation(), position));
 259             }
 260         }
 261     }
 262
 263     // ------------------------------------------------------------------------
 264     // ITmfTraceIndexer - seekIndex
 265     // ------------------------------------------------------------------------
 266
 267     /**
 268      * @since 2.0
 269      */
 270     @Override
 271     public synchronized ITmfContext seekIndex(final ITmfTimestamp timestamp) {
 272
 273         // A null timestamp indicates to seek the first event
 274         if (timestamp == null) {
 275             return fTrace.seekEvent(0);
 276         }
 277
 278         // Find the checkpoint at or before the requested timestamp.
 279         // In the very likely event that the timestamp is not at a checkpoint
 280         // boundary, bsearch will return index = (- (insertion point + 1)).
 281         // It is then trivial to compute the index of the previous checkpoint.
 282         long index = fTraceIndex.binarySearch(new TmfCheckpoint(timestamp, null, 0));
 283         if (index < 0) {
 284             index = Math.max(0, -(index + 2));
 285         } else {
 286             // If timestamp was in the list, use previous index to be able to find the
 287             // first event with the same timestamp before the checkpoint
 288             index = Math.max(0, index - 1);
 289         }
 290
 291         // Position the trace at the checkpoint
 292         return restoreCheckpoint(index);
 293     }
 294
 295     @Override
 296     public ITmfContext seekIndex(final long rank) {
 297
 298         // A rank < 0 indicates to seek the first event
 299         if (rank < 0) {
 300             return fTrace.seekEvent(0);
 301         }
 302
 303         // Find the checkpoint at or before the requested rank.
 304         final int index = (int) rank / fCheckpointInterval;
 305
 306         // Position the trace at the checkpoint
 307         return restoreCheckpoint(index);
 308     }
 309
 310     /**
 311      * Position the trace at the given checkpoint
 312      *
 313      * @param checkpoint the checkpoint index
 314      * @return the corresponding context
 315      */
 316     private ITmfContext restoreCheckpoint(final long checkpoint) {
 317         ITmfLocation location = null;
 318         long index = 0;
 319         synchronized (fTraceIndex) {
 320             if (!fTraceIndex.isEmpty()) {
 321                 index = checkpoint;
 322                 if (index >= fTraceIndex.size()) {
 323                     index = fTraceIndex.size() - 1;
 324                 }
 325                 location = fTraceIndex.get(index).getLocation();
 326             }
 327         }
 328         final ITmfContext context = fTrace.seekEvent(location);
 329         context.setRank(index * fCheckpointInterval);
 330         return context;
 331     }
 332
 333     // ------------------------------------------------------------------------
 334     // Getters
 335     // ------------------------------------------------------------------------
 336
 337     /**
 338      * @return the trace index
 339      * @since 3.0
 340      */
 341     protected ITmfCheckpointIndex getTraceIndex() {
 342         return fTraceIndex;
 343     }
 344
 345 }