org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/trace/TmfTraceIndexer.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.Collections;
  16 import java.util.Vector;
  17
  18 import org.eclipse.core.runtime.IProgressMonitor;
  19 import org.eclipse.core.runtime.IStatus;
  20 import org.eclipse.core.runtime.Status;
  21 import org.eclipse.core.runtime.jobs.Job;
  22 import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
  23 import org.eclipse.linuxtools.tmf.core.event.ITmfTimestamp;
  24 import org.eclipse.linuxtools.tmf.core.event.TmfTimeRange;
  25 import org.eclipse.linuxtools.tmf.core.event.TmfTimestamp;
  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  * <b><u>TmfTraceIndexer</u></b>
  34  * <p>
  35  * A simple trace indexer that builds an array of trace checkpoints. Checkpoints
  36  * are stored at fixed intervals (event rank) in 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 public class TmfTraceIndexer<T extends ITmfTrace<ITmfEvent>> implements ITmfTraceIndexer<T> {
  47
  48     // ------------------------------------------------------------------------
  49     // Attributes
  50     // ------------------------------------------------------------------------
  51
  52     /**
  53      * The event trace to index
  54      */
  55     private final ITmfTrace<ITmfEvent> fTrace;
  56
  57     /**
  58      * The interval between checkpoints
  59      */
  60     protected final int fCheckpointInterval;
  61
  62     /**
  63      * The trace index. It is composed of checkpoints taken at intervals of
  64      * fCheckpointInterval events.
  65      */
  66     protected final Vector<TmfCheckpoint> fTraceIndex;
  67
  68     // ------------------------------------------------------------------------
  69     // Construction
  70     // ------------------------------------------------------------------------
  71
  72     /**
  73      * Basic constructor that uses the default trace block size as checkpoints
  74      * intervals
  75      *
  76      * @param trace the trace to index
  77      */
  78     public TmfTraceIndexer(final ITmfTrace<ITmfEvent> trace) {
  79         this(trace, TmfTrace.DEFAULT_BLOCK_SIZE);
  80     }
  81
  82     /**
  83      * Full trace indexer
  84      *
  85      * @param trace the trace to index
  86      * @param interval the checkpoints interval
  87      */
  88     public TmfTraceIndexer(final ITmfTrace<ITmfEvent> trace, final int interval) {
  89         fTrace = trace;
  90         fCheckpointInterval = interval;
  91         fTraceIndex = new Vector<TmfCheckpoint>();
  92     }
  93
  94     // ------------------------------------------------------------------------
  95     // ITmfTraceIndexer
  96     // ------------------------------------------------------------------------
  97
  98     /* (non-Javadoc)
  99      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTrace#indexTrace(boolean)
 100      *
 101      * The index is a list of contexts that point to events at regular interval
 102      * (rank-wise) in the trace. After it is built, the index can be used to
 103      * quickly access any event by rank or timestamp (using seekIndex()).
 104      *
 105      * The index is built simply by reading the trace
 106      */
 107     @Override
 108     public void buildIndex(final boolean waitForCompletion) {
 109
 110         // The monitoring job
 111         final Job job = new Job("Indexing " + fTrace.getName() + "...") { //$NON-NLS-1$ //$NON-NLS-2$
 112             @Override
 113             protected IStatus run(final IProgressMonitor monitor) {
 114                 while (!monitor.isCanceled()) {
 115                     try {
 116                         Thread.sleep(100);
 117                     } catch (final InterruptedException e) {
 118                         return Status.OK_STATUS;
 119                     }
 120                 }
 121                 monitor.done();
 122                 return Status.OK_STATUS;
 123             }
 124         };
 125         job.schedule();
 126
 127         // Clear the checkpoints
 128         fTraceIndex.clear();
 129
 130         // Build a background request for all the trace data. The index is
 131         // updated as we go by getNextEvent().
 132         final ITmfEventRequest<ITmfEvent> request = new TmfEventRequest<ITmfEvent>(ITmfEvent.class, TmfTimeRange.ETERNITY,
 133                 TmfDataRequest.ALL_DATA, fCheckpointInterval, ITmfDataRequest.ExecutionType.BACKGROUND)
 134                 {
 135             ITmfTimestamp startTime = null;
 136             ITmfTimestamp lastTime = null;
 137
 138             @Override
 139             public void handleData(final ITmfEvent event) {
 140                 super.handleData(event);
 141                 if (event != null) {
 142                     final ITmfTimestamp timestamp = event.getTimestamp();
 143                     if (startTime == null) {
 144                         startTime = timestamp.clone();
 145                     }
 146                     lastTime = timestamp.clone();
 147
 148                     // Update the trace status at regular intervals
 149                     if ((getNbRead() % fCheckpointInterval) == 0) {
 150                         updateTraceStatus();
 151                     }
 152                 }
 153             }
 154
 155             @Override
 156             public void handleSuccess() {
 157                 updateTraceStatus();
 158             }
 159
 160             @Override
 161             public void handleCompleted() {
 162                 job.cancel();
 163                 super.handleCompleted();
 164             }
 165
 166             private void updateTraceStatus() {
 167                 if (getNbRead() != 0) {
 168                     notifyListeners(startTime, lastTime);
 169                 }
 170             }
 171                 };
 172
 173                 // Submit the request and wait for completion if required
 174                 fTrace.sendRequest(request);
 175                 if (waitForCompletion) {
 176                     try {
 177                         request.waitForCompletion();
 178                     } catch (final InterruptedException e) {
 179                     }
 180                 }
 181     }
 182
 183
 184     /* (non-Javadoc)
 185      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#seekIndex(org.eclipse.linuxtools.tmf.core.event.ITmfTimestamp)
 186      */
 187     @Override
 188     public ITmfContext seekIndex(final ITmfTimestamp timestamp) {
 189         // Adjust the timestamp if needed
 190         ITmfTimestamp ts = timestamp;
 191         if (ts == null) {
 192             ts = TmfTimestamp.BIG_BANG;
 193         }
 194
 195         // First, find the right checkpoint
 196         int index = Collections.binarySearch(fTraceIndex, new TmfCheckpoint(ts, null));
 197
 198         // In the very likely case that the checkpoint was not found, bsearch
 199         // returns its negated would-be location (not an offset...). From that
 200         // index, we can then position the stream and get figure out the context.
 201         if (index < 0) {
 202             index = Math.max(0, -(index + 2));
 203         }
 204
 205         // Position the trace at the checkpoint
 206         ITmfLocation<?> location;
 207         synchronized (fTraceIndex) {
 208             if (!fTraceIndex.isEmpty()) {
 209                 if (index >= fTraceIndex.size()) {
 210                     index = fTraceIndex.size() - 1;
 211                 }
 212                 location = fTraceIndex.elementAt(index).getLocation();
 213             } else {
 214                 location = null;
 215             }
 216         }
 217         final ITmfContext context = fTrace.seekLocation(location);
 218         context.setRank(index * fCheckpointInterval);
 219
 220         return context;
 221     }
 222
 223     @Override
 224     public ITmfContext seekIndex(final long rank) {
 225
 226         // Position the stream at the previous checkpoint
 227         int index = (int) rank / fCheckpointInterval;
 228         ITmfLocation<?> location;
 229         synchronized (fTraceIndex) {
 230             if (fTraceIndex.isEmpty()) {
 231                 location = null;
 232             } else {
 233                 if (index >= fTraceIndex.size()) {
 234                     index = fTraceIndex.size() - 1;
 235                 }
 236                 location = fTraceIndex.elementAt(index).getLocation();
 237             }
 238         }
 239
 240         final ITmfContext context = fTrace.seekLocation(location);
 241         final long pos = index * fCheckpointInterval;
 242         context.setRank(pos);
 243
 244         return context;
 245     }
 246
 247     private void notifyListeners(final ITmfTimestamp startTime, final ITmfTimestamp endTime) {
 248         fTrace.broadcast(new TmfTraceUpdatedSignal(fTrace, fTrace, new TmfTimeRange(startTime, endTime)));
 249     }
 250
 251     @Override
 252     public void updateIndex(final ITmfContext context, final long rank, final ITmfTimestamp timestamp) {
 253         if ((rank % fCheckpointInterval) == 0) {
 254             // Determine the table position
 255             final long position = rank / fCheckpointInterval;
 256             // Add new entry at proper location (if empty)
 257             if (fTraceIndex.size() == position) {
 258                 final ITmfLocation<?> location = context.getLocation().clone();
 259                 fTraceIndex.add(new TmfCheckpoint(timestamp.clone(), location));
 260                 // System.out.println(getName() + "[" + (fCheckpoints.size() - 1) + "] " + timestamp + ", " + location.toString());
 261             }
 262         }
 263     }
 264
 265 }