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.trace.TmfExperimentContext;
  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     protected final ITmfTrace<ITmfEvent> fTrace;
  60
  61     // The interval between checkpoints
  62     private final int fCheckpointInterval;
  63
  64     // The event trace to index
  65     private boolean fIsIndexing;
  66
  67     /**
  68      * The trace index. It is composed of checkpoints taken at intervals of
  69      * fCheckpointInterval events.
  70      */
  71     protected final List<ITmfCheckpoint> fTraceIndex;
  72
  73     /**
  74      * The indexing request
  75      */
  76     private ITmfEventRequest<ITmfEvent> fIndexingRequest = null;
  77
  78     // ------------------------------------------------------------------------
  79     // Construction
  80     // ------------------------------------------------------------------------
  81
  82     /**
  83      * Basic constructor that uses the default trace block size as checkpoints
  84      * intervals
  85      *
  86      * @param trace the trace to index
  87      */
  88     public TmfCheckpointIndexer(final ITmfTrace<ITmfEvent> trace) {
  89         this(trace, TmfTrace.DEFAULT_BLOCK_SIZE);
  90     }
  91
  92     /**
  93      * Full trace indexer
  94      *
  95      * @param trace the trace to index
  96      * @param interval the checkpoints interval
  97      */
  98     public TmfCheckpointIndexer(final ITmfTrace<ITmfEvent> trace, final int interval) {
  99         fTrace = trace;
 100         fCheckpointInterval = interval;
 101         fTraceIndex = new ArrayList<ITmfCheckpoint>();
 102         fIsIndexing = false;
 103     }
 104
 105     /* (non-Javadoc)
 106      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#dispose()
 107      */
 108     @Override
 109     public void dispose() {
 110         if ((fIndexingRequest != null) && !fIndexingRequest.isCompleted()) {
 111             fIndexingRequest.cancel();
 112             fTraceIndex.clear();
 113         }
 114     }
 115
 116     // ------------------------------------------------------------------------
 117     // ITmfTraceIndexer - isIndexing
 118     // ------------------------------------------------------------------------
 119
 120     /* (non-Javadoc)
 121      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#isIndexing()
 122      */
 123     @Override
 124     public boolean isIndexing() {
 125         return fIsIndexing;
 126     }
 127
 128     // ------------------------------------------------------------------------
 129     // ITmfTraceIndexer - buildIndex
 130     // ------------------------------------------------------------------------
 131
 132     /* (non-Javadoc)
 133      *
 134      * The index is a list of contexts that point to events at regular interval
 135      * (rank-wise) in the trace. After it is built, the index can be used to
 136      * quickly access any event by rank or timestamp (using seekIndex()).
 137      *
 138      * The index is built simply by reading the trace
 139      *
 140      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#buildIndex(long, org.eclipse.linuxtools.tmf.core.event.TmfTimeRange, boolean)
 141      */
 142     @Override
 143     public void buildIndex(final long offset, final TmfTimeRange range, final boolean waitForCompletion) {
 144
 145         // Don't do anything if we are already indexing
 146         synchronized (fTraceIndex) {
 147             if (fIsIndexing) {
 148                 return;
 149             }
 150             fIsIndexing = true;
 151         }
 152
 153         // The monitoring job
 154         final Job job = new Job("Indexing " + fTrace.getName() + "...") { //$NON-NLS-1$ //$NON-NLS-2$
 155             @Override
 156             protected IStatus run(final IProgressMonitor monitor) {
 157                 while (!monitor.isCanceled()) {
 158                     try {
 159                         Thread.sleep(100);
 160                     } catch (final InterruptedException e) {
 161                         return Status.OK_STATUS;
 162                     }
 163                 }
 164                 monitor.done();
 165                 return Status.OK_STATUS;
 166             }
 167         };
 168         job.schedule();
 169
 170         // Build a background request for all the trace data. The index is
 171         // updated as we go by readNextEvent().
 172         fIndexingRequest = new TmfEventRequest<ITmfEvent>(ITmfEvent.class,
 173                 range, offset, TmfDataRequest.ALL_DATA, fCheckpointInterval, ITmfDataRequest.ExecutionType.BACKGROUND)
 174         {
 175             private ITmfTimestamp startTime = null;
 176             private ITmfTimestamp lastTime = null;
 177
 178             @Override
 179             public void handleData(final ITmfEvent event) {
 180                 super.handleData(event);
 181                 if (event != null) {
 182                     final ITmfTimestamp timestamp = event.getTimestamp();
 183                     if (startTime == null) {
 184                         startTime = timestamp.clone();
 185                     }
 186                     lastTime = timestamp.clone();
 187
 188                     // Update the trace status at regular intervals
 189                     if ((getNbRead() % fCheckpointInterval) == 0) {
 190                         updateTraceStatus();
 191                     }
 192                 }
 193             }
 194
 195             @Override
 196             public void handleSuccess() {
 197                 updateTraceStatus();
 198             }
 199
 200             @Override
 201             public void handleCompleted() {
 202                 job.cancel();
 203                 super.handleCompleted();
 204                 fIsIndexing = false;
 205             }
 206
 207             private void updateTraceStatus() {
 208                 if (getNbRead() != 0) {
 209                     signalNewTimeRange(startTime, lastTime);
 210                 }
 211             }
 212         };
 213
 214         // Submit the request and wait for completion if required
 215         fTrace.sendRequest(fIndexingRequest);
 216         if (waitForCompletion) {
 217             try {
 218                 fIndexingRequest.waitForCompletion();
 219             } catch (final InterruptedException e) {
 220             }
 221         }
 222     }
 223
 224     /**
 225      * Notify the interested parties that the trace time range has changed
 226      *
 227      * @param startTime the new start time
 228      * @param endTime the new end time
 229      */
 230     private void signalNewTimeRange(final ITmfTimestamp startTime, final ITmfTimestamp endTime) {
 231         fTrace.broadcast(new TmfTraceUpdatedSignal(fTrace, fTrace, new TmfTimeRange(startTime, endTime)));
 232     }
 233
 234     // ------------------------------------------------------------------------
 235     // ITmfTraceIndexer - updateIndex
 236     // ------------------------------------------------------------------------
 237
 238     /* (non-Javadoc)
 239      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#updateIndex(org.eclipse.linuxtools.tmf.core.trace.ITmfContext, org.eclipse.linuxtools.tmf.core.event.ITmfTimestamp)
 240      */
 241     @Override
 242     public synchronized void updateIndex(final ITmfContext context, final ITmfTimestamp timestamp) {
 243         final long rank = context.getRank();
 244         if ((rank % fCheckpointInterval) == 0) {
 245             // Determine the table position
 246             final long position = rank / fCheckpointInterval;
 247             // Add new entry at proper location (if empty)
 248             if (fTraceIndex.size() == position) {
 249                 fTraceIndex.add(new TmfCheckpoint(timestamp.clone(), shrinkContext(context)));
 250             }
 251         }
 252     }
 253
 254     // ------------------------------------------------------------------------
 255     // ITmfTraceIndexer - seekIndex
 256     // ------------------------------------------------------------------------
 257
 258     /* (non-Javadoc)
 259      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#seekIndex(org.eclipse.linuxtools.tmf.core.event.ITmfTimestamp)
 260      */
 261     @Override
 262     public synchronized ITmfContext seekIndex(final ITmfTimestamp timestamp) {
 263
 264         // A null timestamp indicates to seek the first event
 265         if (timestamp == null) {
 266             return fTrace.seekEvent(0);
 267         }
 268
 269         // Find the checkpoint at or before the requested timestamp.
 270         // In the very likely event that the timestamp is not at a checkpoint
 271         // boundary, bsearch will return index = (- (insertion point + 1)).
 272         // It is then trivial to compute the index of the previous checkpoint.
 273         int index = Collections.binarySearch(fTraceIndex, new TmfCheckpoint(timestamp, null));
 274         if (index < 0) {
 275             index = Math.max(0, -(index + 2));
 276         }
 277
 278         // Position the trace at the checkpoint
 279         return restoreCheckpoint(index);
 280     }
 281
 282     /* (non-Javadoc)
 283      * @see org.eclipse.linuxtools.tmf.core.trace.ITmfTraceIndexer#seekIndex(long)
 284      */
 285     @Override
 286     public ITmfContext seekIndex(final long rank) {
 287
 288         // A rank < 0 indicates to seek the first event
 289         if (rank < 0) {
 290             return fTrace.seekEvent(0);
 291         }
 292
 293         // Find the checkpoint at or before the requested rank.
 294         final int index = (int) rank / fCheckpointInterval;
 295
 296         // Position the trace at the checkpoint
 297         return restoreCheckpoint(index);
 298     }
 299
 300     /**
 301      * Position the trace at the given checkpoint
 302      *
 303      * @param checkpoint the checkpoint index
 304      * @return the corresponding context
 305      */
 306     private ITmfContext restoreCheckpoint(final int checkpoint) {
 307         ITmfLocation<?> location = null;
 308         int index = 0;
 309         synchronized (fTraceIndex) {
 310             if (!fTraceIndex.isEmpty()) {
 311                 index = checkpoint;
 312                 if (index >= fTraceIndex.size()) {
 313                     index = fTraceIndex.size() - 1;
 314                 }
 315                 return restoreContext(fTraceIndex.get(index).getContext());
 316             }
 317         }
 318         final ITmfContext context = fTrace.seekEvent(location);
 319         context.setRank((long) index * fCheckpointInterval);
 320         return context;
 321     }
 322
 323     // ------------------------------------------------------------------------
 324     // Getters
 325     // ------------------------------------------------------------------------
 326
 327     /**
 328      * @return the trace index
 329      */
 330     protected List<ITmfCheckpoint> getTraceIndex() {
 331         return fTraceIndex;
 332     }
 333
 334     // ------------------------------------------------------------------------
 335     // Context conversion functions
 336     // ------------------------------------------------------------------------
 337
 338     private ITmfContext shrinkContext(ITmfContext context) {
 339         if (context instanceof TmfExperimentContext) {
 340             return shrinkExpContext(context);
 341         }
 342         TmfContext ctx = new TmfContext(context.getLocation().clone(), context.getRank());
 343         return ctx;
 344     }
 345
 346     private ITmfContext shrinkExpContext(ITmfContext context) {
 347         TmfExperimentContext expContext = (TmfExperimentContext) context;
 348         int size = expContext.getContexts().length;
 349         ITmfContext[] trcCtxts = new TmfContext[size];
 350         for (int i = 0; i < size; i++) {
 351             ITmfContext ctx = expContext.getContexts()[i];
 352             trcCtxts[i] = (ctx != null) ? new TmfContext(ctx.getLocation().clone(), ctx.getRank()) : null;
 353         }
 354         TmfExperimentContext expCtx = new TmfExperimentContext(trcCtxts);
 355         expCtx.setLocation(context.getLocation().clone());
 356         expCtx.setRank(context.getRank());
 357         ITmfEvent[] trcEvts = expCtx.getEvents();
 358         for (int i = 0; i < size; i++) {
 359             ITmfEvent event = expContext.getEvents()[i];
 360             trcEvts[i] = (event != null) ? event.clone() : null;
 361         }
 362         return expCtx;
 363     }
 364
 365     private ITmfContext restoreContext(ITmfContext context) {
 366         if (context instanceof TmfExperimentContext) {
 367             return restoreExpContext(context);
 368         }
 369         ITmfContext ctx = fTrace.seekEvent(context.getLocation());
 370         ctx.setRank(context.getRank());
 371         return ctx;
 372     }
 373
 374     private ITmfContext restoreExpContext(ITmfContext context) {
 375         TmfExperimentContext expContext = (TmfExperimentContext) context;
 376         int size = expContext.getContexts().length;
 377         ITmfContext[] trcCtxts = new ITmfContext[size];
 378         for (int i = 0; i < size; i++) {
 379             ITmfTrace<?> trace = ((TmfExperiment<?>) fTrace).getTraces()[i];
 380             ITmfContext ctx = expContext.getContexts()[i];
 381             trcCtxts[i] = trace.seekEvent(ctx.getLocation().clone());
 382             trcCtxts[i].setRank(ctx.getRank());
 383         }
 384         TmfExperimentContext ctx = new TmfExperimentContext(trcCtxts);
 385         ctx.setLocation(context.getLocation().clone());
 386         ctx.setRank(context.getRank());
 387         ITmfEvent[] trcEvts = expContext.getEvents();
 388         for (int i = 0; i < size; i++) {
 389             ITmfEvent event = trcEvts[i];
 390             ctx.getEvents()[i] = (event != null) ? event.clone() : null;
 391         }
 392         return ctx;
 393     }
 394 }