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