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