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

   1 /*******************************************************************************
   2  * Copyright (c) 2012 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;
  14
  15 import java.util.ArrayList;
  16 import java.util.Collections;
  17 import java.util.List;
  18
  19 import org.eclipse.core.runtime.IProgressMonitor;
  20 import org.eclipse.core.runtime.IStatus;
  21 import org.eclipse.core.runtime.Status;
  22 import org.eclipse.core.runtime.jobs.Job;
  23 import org.eclipse.linuxtools.internal.tmf.core.Messages;
  24 import org.eclipse.linuxtools.tmf.core.component.TmfDataProvider;
  25 import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
  26 import org.eclipse.linuxtools.tmf.core.request.ITmfDataRequest;
  27 import org.eclipse.linuxtools.tmf.core.request.ITmfEventRequest;
  28 import org.eclipse.linuxtools.tmf.core.request.TmfDataRequest;
  29 import org.eclipse.linuxtools.tmf.core.request.TmfEventRequest;
  30 import org.eclipse.linuxtools.tmf.core.signal.TmfTraceUpdatedSignal;
  31 import org.eclipse.linuxtools.tmf.core.timestamp.ITmfTimestamp;
  32 import org.eclipse.linuxtools.tmf.core.timestamp.TmfTimeRange;
  33
  34 /**
  35  * A simple indexer that manages the trace index as an array of trace
  36  * checkpoints. Checkpoints are stored at fixed intervals (event rank) in
  37  * ascending timestamp order.
  38  * <p>
  39  * The goal being to access a random trace event reasonably fast from the user's
  40  * standpoint, picking the right interval value becomes a trade-off between speed
  41  * and memory usage (a shorter inter-event interval is faster but requires more
  42  * checkpoints).
  43  * <p>
  44  * Locating a specific checkpoint is trivial for both rank (rank % interval) and
  45  * timestamp (bsearch in the array).
  46  *
  47  * @version 1.0
  48  * @author Francois Chouinard
  49  *
  50  * @see ITmfTrace
  51  * @see ITmfEvent
  52  */
  53 public class TmfCheckpointIndexer implements ITmfTraceIndexer {
  54
  55     // ------------------------------------------------------------------------
  56     // Attributes
  57     // ------------------------------------------------------------------------
  58
  59     /** The event trace to index */
  60     protected final ITmfTrace fTrace;
  61
  62     /** The interval between checkpoints */
  63     private final int fCheckpointInterval;
  64
  65     /** The event trace to index */
  66     private boolean fIsIndexing;
  67
  68     /**
  69      * The trace index. It is composed of checkpoints taken at intervals of
  70      * fCheckpointInterval events.
  71      */
  72     protected final List<ITmfCheckpoint> fTraceIndex;
  73
  74     /**
  75      * The indexing request
  76      */
  77     private ITmfEventRequest fIndexingRequest = null;
  78
  79     // ------------------------------------------------------------------------
  80     // Construction
  81     // ------------------------------------------------------------------------
  82
  83     /**
  84      * Basic constructor that uses the default trace block size as checkpoints
  85      * intervals
  86      *
  87      * @param trace the trace to index
  88      */
  89     public TmfCheckpointIndexer(final ITmfTrace trace) {
  90         this(trace, TmfDataProvider.DEFAULT_BLOCK_SIZE);
  91     }
  92
  93     /**
  94      * Full trace indexer
  95      *
  96      * @param trace the trace to index
  97      * @param interval the checkpoints interval
  98      */
  99     public TmfCheckpointIndexer(final ITmfTrace trace, final int interval) {
 100         fTrace = trace;
 101         fCheckpointInterval = interval;
 102         fTraceIndex = new ArrayList<ITmfCheckpoint>();
 103         fIsIndexing = false;
 104     }
 105
 106     /* (non-Javadoc)
 107      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#dispose()
 108      */
 109     @Override
 110     public void dispose() {
 111         if ((fIndexingRequest != null) && !fIndexingRequest.isCompleted()) {
 112             fIndexingRequest.cancel();
 113             fTraceIndex.clear();
 114         }
 115     }
 116
 117     // ------------------------------------------------------------------------
 118     // ITmfTraceIndexer - isIndexing
 119     // ------------------------------------------------------------------------
 120
 121     /* (non-Javadoc)
 122      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#isIndexing()
 123      */
 124     @Override
 125     public boolean isIndexing() {
 126         return fIsIndexing;
 127     }
 128
 129     // ------------------------------------------------------------------------
 130     // ITmfTraceIndexer - buildIndex
 131     // ------------------------------------------------------------------------
 132
 133     /**
 134      * @since 2.0
 135      */
 136     @Override
 137     public void buildIndex(final long offset, final TmfTimeRange range, final boolean waitForCompletion) {
 138
 139         // Don't do anything if we are already indexing
 140         synchronized (fTraceIndex) {
 141             if (fIsIndexing) {
 142                 return;
 143             }
 144             fIsIndexing = true;
 145         }
 146
 147         // The monitoring job
 148         final Job job = new Job("Indexing " + fTrace.getName() + "...") { //$NON-NLS-1$ //$NON-NLS-2$
 149             @Override
 150             protected IStatus run(final IProgressMonitor monitor) {
 151                 monitor.beginTask("", IProgressMonitor.UNKNOWN); //$NON-NLS-1$
 152                 while (!monitor.isCanceled()) {
 153                     try {
 154                         long prevNbEvents = fTrace.getNbEvents();
 155                         Thread.sleep(250);
 156                         long nbEvents = fTrace.getNbEvents();
 157                         setName(Messages.TmfCheckpointIndexer_Indexing + ' ' + fTrace.getName() + " (" + nbEvents + ")"); //$NON-NLS-1$ //$NON-NLS-2$
 158                         // setName doesn't refresh the UI, setTaskName does
 159                         long rate = (nbEvents - prevNbEvents) * 4;
 160                         monitor.setTaskName(rate + " " + Messages.TmfCheckpointIndexer_EventsPerSecond); //$NON-NLS-1$
 161                     } catch (final InterruptedException e) {
 162                         return Status.OK_STATUS;
 163                     }
 164                 }
 165                 monitor.done();
 166                 return Status.OK_STATUS;
 167             }
 168         };
 169         job.schedule();
 170
 171         // Build a background request for all the trace data. The index is
 172         // updated as we go by readNextEvent().
 173         fIndexingRequest = new TmfEventRequest(ITmfEvent.class,
 174                 range, offset, TmfDataRequest.ALL_DATA, fCheckpointInterval, ITmfDataRequest.ExecutionType.BACKGROUND)
 175         {
 176             @Override
 177             public void handleData(final ITmfEvent event) {
 178                 super.handleData(event);
 179                 if (event != null) {
 180                     // Update the trace status at regular intervals
 181                     if ((getNbRead() % fCheckpointInterval) == 0) {
 182                         updateTraceStatus();
 183                     }
 184                 }
 185             }
 186
 187             @Override
 188             public void handleSuccess() {
 189                 updateTraceStatus();
 190             }
 191
 192             @Override
 193             public void handleCompleted() {
 194                 job.cancel();
 195                 super.handleCompleted();
 196                 fIsIndexing = false;
 197             }
 198
 199             private void updateTraceStatus() {
 200                 if (fTrace.getNbEvents() > 0) {
 201                     signalNewTimeRange(fTrace.getStartTime(), fTrace.getEndTime());
 202                 }
 203             }
 204         };
 205
 206         // Submit the request and wait for completion if required
 207         fTrace.sendRequest(fIndexingRequest);
 208         if (waitForCompletion) {
 209             try {
 210                 fIndexingRequest.waitForCompletion();
 211             } catch (final InterruptedException e) {
 212             }
 213         }
 214     }
 215
 216     /**
 217      * Notify the interested parties that the trace time range has changed
 218      *
 219      * @param startTime the new start time
 220      * @param endTime the new end time
 221      */
 222     private void signalNewTimeRange(final ITmfTimestamp startTime, final ITmfTimestamp endTime) {
 223         fTrace.broadcast(new TmfTraceUpdatedSignal(fTrace, fTrace, new TmfTimeRange(startTime, endTime)));
 224     }
 225
 226     // ------------------------------------------------------------------------
 227     // ITmfTraceIndexer - updateIndex
 228     // ------------------------------------------------------------------------
 229
 230     /**
 231      * @since 2.0
 232      */
 233     @Override
 234     public synchronized void updateIndex(final ITmfContext context, final ITmfTimestamp timestamp) {
 235         if ((context.getRank() % fCheckpointInterval) == 0) {
 236             // Determine the table position
 237             final long position = context.getRank() / fCheckpointInterval;
 238             // Add new entry at proper location (if empty)
 239             if (fTraceIndex.size() == position) {
 240                 fTraceIndex.add(new TmfCheckpoint(timestamp, context.getLocation()));
 241             }
 242         }
 243     }
 244
 245     // ------------------------------------------------------------------------
 246     // ITmfTraceIndexer - seekIndex
 247     // ------------------------------------------------------------------------
 248
 249     /**
 250      * @since 2.0
 251      */
 252     @Override
 253     public synchronized ITmfContext seekIndex(final ITmfTimestamp timestamp) {
 254
 255         // A null timestamp indicates to seek the first event
 256         if (timestamp == null) {
 257             return fTrace.seekEvent(0);
 258         }
 259
 260         // Find the checkpoint at or before the requested timestamp.
 261         // In the very likely event that the timestamp is not at a checkpoint
 262         // boundary, bsearch will return index = (- (insertion point + 1)).
 263         // It is then trivial to compute the index of the previous checkpoint.
 264         int index = Collections.binarySearch(fTraceIndex, new TmfCheckpoint(timestamp, null));
 265         if (index < 0) {
 266             index = Math.max(0, -(index + 2));
 267         } else {
 268             // If timestamp was in the list, use previous index to be able to find the
 269             // first event with the same timestamp before the checkpoint
 270             index = Math.max(0, index - 1);
 271         }
 272
 273         // Position the trace at the checkpoint
 274         return restoreCheckpoint(index);
 275     }
 276
 277     /* (non-Javadoc)
 278      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#seekIndex(long)
 279      */
 280     @Override
 281     public ITmfContext seekIndex(final long rank) {
 282
 283         // A rank < 0 indicates to seek the first event
 284         if (rank < 0) {
 285             return fTrace.seekEvent(0);
 286         }
 287
 288         // Find the checkpoint at or before the requested rank.
 289         final int index = (int) rank / fCheckpointInterval;
 290
 291         // Position the trace at the checkpoint
 292         return restoreCheckpoint(index);
 293     }
 294
 295     /**
 296      * Position the trace at the given checkpoint
 297      *
 298      * @param checkpoint the checkpoint index
 299      * @return the corresponding context
 300      */
 301     private ITmfContext restoreCheckpoint(final int checkpoint) {
 302         ITmfLocation location = null;
 303         int index = 0;
 304         synchronized (fTraceIndex) {
 305             if (!fTraceIndex.isEmpty()) {
 306                 index = checkpoint;
 307                 if (index >= fTraceIndex.size()) {
 308                     index = fTraceIndex.size() - 1;
 309                 }
 310                 location = fTraceIndex.get(index).getLocation();
 311             }
 312         }
 313         final ITmfContext context = fTrace.seekEvent(location);
 314         context.setRank((long) index * fCheckpointInterval);
 315         return context;
 316     }
 317
 318     // ------------------------------------------------------------------------
 319     // Getters
 320     // ------------------------------------------------------------------------
 321
 322     /**
 323      * @return the trace index
 324      */
 325     protected List<ITmfCheckpoint> getTraceIndex() {
 326         return fTraceIndex;
 327     }
 328
 329 }