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