| 1 | /******************************************************************************* |
| 2 | * Copyright (c) 2013, 2014 Ericsson |
| 3 | * All rights reserved. This program and the accompanying materials are |
| 4 | * made available under the terms of the Eclipse Public License v1.0 which |
| 5 | * accompanies this distribution, and is available at |
| 6 | * http://www.eclipse.org/legal/epl-v10.html |
| 7 | * |
| 8 | * Contributors: |
| 9 | * Alexandre Montplaisir - Initial API and implementation |
| 10 | *******************************************************************************/ |
| 11 | |
| 12 | package org.eclipse.tracecompass.internal.tmf.core.statesystem.backends.partial; |
| 13 | |
| 14 | import java.io.File; |
| 15 | import java.io.FileInputStream; |
| 16 | import java.io.PrintWriter; |
| 17 | import java.util.List; |
| 18 | import java.util.Map; |
| 19 | import java.util.TreeMap; |
| 20 | import java.util.concurrent.CountDownLatch; |
| 21 | |
| 22 | import org.eclipse.jdt.annotation.NonNull; |
| 23 | import org.eclipse.tracecompass.statesystem.core.ITmfStateSystem; |
| 24 | import org.eclipse.tracecompass.statesystem.core.backend.IStateHistoryBackend; |
| 25 | import org.eclipse.tracecompass.statesystem.core.exceptions.AttributeNotFoundException; |
| 26 | import org.eclipse.tracecompass.statesystem.core.exceptions.StateSystemDisposedException; |
| 27 | import org.eclipse.tracecompass.statesystem.core.exceptions.TimeRangeException; |
| 28 | import org.eclipse.tracecompass.statesystem.core.interval.ITmfStateInterval; |
| 29 | import org.eclipse.tracecompass.statesystem.core.interval.TmfStateInterval; |
| 30 | import org.eclipse.tracecompass.statesystem.core.statevalue.ITmfStateValue; |
| 31 | import org.eclipse.tracecompass.tmf.core.event.ITmfEvent; |
| 32 | import org.eclipse.tracecompass.tmf.core.request.ITmfEventRequest; |
| 33 | import org.eclipse.tracecompass.tmf.core.request.TmfEventRequest; |
| 34 | import org.eclipse.tracecompass.tmf.core.statesystem.AbstractTmfStateProvider; |
| 35 | import org.eclipse.tracecompass.tmf.core.statesystem.ITmfStateProvider; |
| 36 | import org.eclipse.tracecompass.tmf.core.timestamp.ITmfTimestamp; |
| 37 | import org.eclipse.tracecompass.tmf.core.timestamp.TmfTimeRange; |
| 38 | import org.eclipse.tracecompass.tmf.core.timestamp.TmfTimestamp; |
| 39 | import org.eclipse.tracecompass.tmf.core.trace.ITmfTrace; |
| 40 | |
| 41 | /** |
| 42 | * Partial state history back-end. |
| 43 | * |
| 44 | * This is a shim inserted between the real state system and a "real" history |
| 45 | * back-end. It will keep checkpoints, every n trace events (where n is called |
| 46 | * the granularity) and will only forward to the real state history the state |
| 47 | * intervals that crosses at least one checkpoint. Every other interval will |
| 48 | * be discarded. |
| 49 | * |
| 50 | * This would mean that it can only answer queries exactly at the checkpoints. |
| 51 | * For any other timestamps (ie, most of the time), it will load the closest |
| 52 | * earlier checkpoint, and will re-feed the state-change-input with events from |
| 53 | * the trace, to restore the real state at the time that was requested. |
| 54 | * |
| 55 | * @author Alexandre Montplaisir |
| 56 | */ |
| 57 | public class PartialHistoryBackend implements IStateHistoryBackend { |
| 58 | |
| 59 | private final @NonNull String fSSID; |
| 60 | |
| 61 | /** |
| 62 | * A partial history needs the state input plugin to re-generate state |
| 63 | * between checkpoints. |
| 64 | */ |
| 65 | private final @NonNull ITmfStateProvider fPartialInput; |
| 66 | |
| 67 | /** |
| 68 | * Fake state system that is used for partially rebuilding the states (when |
| 69 | * going from a checkpoint to a target query timestamp). |
| 70 | */ |
| 71 | private final @NonNull PartialStateSystem fPartialSS; |
| 72 | |
| 73 | /** Reference to the "real" state history that is used for storage */ |
| 74 | private final @NonNull IStateHistoryBackend fInnerHistory; |
| 75 | |
| 76 | /** Checkpoints map, <Timestamp, Rank in the trace> */ |
| 77 | private final @NonNull TreeMap<Long, Long> fCheckpoints = new TreeMap<>(); |
| 78 | |
| 79 | /** Latch tracking if the initial checkpoint registration is done */ |
| 80 | private final @NonNull CountDownLatch fCheckpointsReady = new CountDownLatch(1); |
| 81 | |
| 82 | private final long fGranularity; |
| 83 | |
| 84 | private long fLatestTime; |
| 85 | |
| 86 | /** |
| 87 | * Constructor |
| 88 | * |
| 89 | * @param ssid |
| 90 | * The state system's ID |
| 91 | * @param partialInput |
| 92 | * The state change input object that was used to build the |
| 93 | * upstream state system. This partial history will make its own |
| 94 | * copy (since they have different targets). |
| 95 | * @param pss |
| 96 | * The partial history's inner state system. It should already be |
| 97 | * assigned to partialInput. |
| 98 | * @param realBackend |
| 99 | * The real state history back-end to use. It's supposed to be |
| 100 | * modular, so it should be able to be of any type. |
| 101 | * @param granularity |
| 102 | * Configuration parameter indicating how many trace events there |
| 103 | * should be between each checkpoint |
| 104 | */ |
| 105 | public PartialHistoryBackend(@NonNull String ssid, |
| 106 | ITmfStateProvider partialInput, |
| 107 | PartialStateSystem pss, |
| 108 | IStateHistoryBackend realBackend, |
| 109 | long granularity) { |
| 110 | if (granularity <= 0 || partialInput == null || pss == null || |
| 111 | partialInput.getAssignedStateSystem() != pss) { |
| 112 | throw new IllegalArgumentException(); |
| 113 | } |
| 114 | |
| 115 | final long startTime = realBackend.getStartTime(); |
| 116 | |
| 117 | fSSID = ssid; |
| 118 | fPartialInput = partialInput; |
| 119 | fPartialSS = pss; |
| 120 | |
| 121 | fInnerHistory = realBackend; |
| 122 | fGranularity = granularity; |
| 123 | |
| 124 | fLatestTime = startTime; |
| 125 | |
| 126 | registerCheckpoints(); |
| 127 | } |
| 128 | |
| 129 | private void registerCheckpoints() { |
| 130 | ITmfEventRequest request = new CheckpointsRequest(fPartialInput, fCheckpoints); |
| 131 | fPartialInput.getTrace().sendRequest(request); |
| 132 | /* The request will countDown the checkpoints latch once it's finished */ |
| 133 | } |
| 134 | |
| 135 | @Override |
| 136 | public String getSSID() { |
| 137 | return fSSID; |
| 138 | } |
| 139 | |
| 140 | @Override |
| 141 | public long getStartTime() { |
| 142 | return fInnerHistory.getStartTime(); |
| 143 | } |
| 144 | |
| 145 | @Override |
| 146 | public long getEndTime() { |
| 147 | return fLatestTime; |
| 148 | } |
| 149 | |
| 150 | @Override |
| 151 | public void insertPastState(long stateStartTime, long stateEndTime, |
| 152 | int quark, ITmfStateValue value) throws TimeRangeException { |
| 153 | waitForCheckpoints(); |
| 154 | |
| 155 | /* Update the latest time */ |
| 156 | if (stateEndTime > fLatestTime) { |
| 157 | fLatestTime = stateEndTime; |
| 158 | } |
| 159 | |
| 160 | /* |
| 161 | * Check if the interval intersects the previous checkpoint. If so, |
| 162 | * insert it in the real history back-end. |
| 163 | * |
| 164 | * FIXME since intervals are inserted in order of rank, we could avoid |
| 165 | * doing a map lookup every time here (just compare with the known |
| 166 | * previous one). |
| 167 | */ |
| 168 | if (stateStartTime <= fCheckpoints.floorKey(stateEndTime)) { |
| 169 | fInnerHistory.insertPastState(stateStartTime, stateEndTime, quark, value); |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | @Override |
| 174 | public void finishedBuilding(long endTime) throws TimeRangeException { |
| 175 | fInnerHistory.finishedBuilding(endTime); |
| 176 | } |
| 177 | |
| 178 | @Override |
| 179 | public FileInputStream supplyAttributeTreeReader() { |
| 180 | return fInnerHistory.supplyAttributeTreeReader(); |
| 181 | } |
| 182 | |
| 183 | @Override |
| 184 | public File supplyAttributeTreeWriterFile() { |
| 185 | return fInnerHistory.supplyAttributeTreeWriterFile(); |
| 186 | } |
| 187 | |
| 188 | @Override |
| 189 | public long supplyAttributeTreeWriterFilePosition() { |
| 190 | return fInnerHistory.supplyAttributeTreeWriterFilePosition(); |
| 191 | } |
| 192 | |
| 193 | @Override |
| 194 | public void removeFiles() { |
| 195 | fInnerHistory.removeFiles(); |
| 196 | } |
| 197 | |
| 198 | @Override |
| 199 | public void dispose() { |
| 200 | fPartialInput.dispose(); |
| 201 | fPartialSS.dispose(); |
| 202 | fInnerHistory.dispose(); |
| 203 | } |
| 204 | |
| 205 | @Override |
| 206 | public void doQuery(List<ITmfStateInterval> currentStateInfo, long t) |
| 207 | throws TimeRangeException, StateSystemDisposedException { |
| 208 | /* Wait for required steps to be done */ |
| 209 | waitForCheckpoints(); |
| 210 | fPartialSS.getUpstreamSS().waitUntilBuilt(); |
| 211 | |
| 212 | if (!checkValidTime(t)) { |
| 213 | throw new TimeRangeException(); |
| 214 | } |
| 215 | |
| 216 | /* Reload the previous checkpoint */ |
| 217 | long checkpointTime = fCheckpoints.floorKey(t); |
| 218 | fInnerHistory.doQuery(currentStateInfo, checkpointTime); |
| 219 | |
| 220 | /* |
| 221 | * Set the initial contents of the partial state system (which is the |
| 222 | * contents of the query at the checkpoint). |
| 223 | */ |
| 224 | fPartialSS.takeQueryLock(); |
| 225 | fPartialSS.replaceOngoingState(currentStateInfo); |
| 226 | |
| 227 | /* Send an event request to update the state system to the target time. */ |
| 228 | TmfTimeRange range = new TmfTimeRange( |
| 229 | /* |
| 230 | * The state at the checkpoint already includes any state change |
| 231 | * caused by the event(s) happening exactly at 'checkpointTime', |
| 232 | * if any. We must not include those events in the query. |
| 233 | */ |
| 234 | new TmfTimestamp(checkpointTime + 1, ITmfTimestamp.NANOSECOND_SCALE), |
| 235 | new TmfTimestamp(t, ITmfTimestamp.NANOSECOND_SCALE)); |
| 236 | ITmfEventRequest request = new PartialStateSystemRequest(fPartialInput, range); |
| 237 | fPartialInput.getTrace().sendRequest(request); |
| 238 | |
| 239 | try { |
| 240 | request.waitForCompletion(); |
| 241 | } catch (InterruptedException e) { |
| 242 | e.printStackTrace(); |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Now the partial state system should have the ongoing time we are |
| 247 | * looking for. However, the method expects a List of *state intervals*, |
| 248 | * not state values, so we'll create intervals with a dummy end time. |
| 249 | */ |
| 250 | try { |
| 251 | for (int i = 0; i < currentStateInfo.size(); i++) { |
| 252 | long start = 0; |
| 253 | ITmfStateValue val = null; |
| 254 | start = ((ITmfStateSystem) fPartialSS).getOngoingStartTime(i); |
| 255 | val = ((ITmfStateSystem) fPartialSS).queryOngoingState(i); |
| 256 | |
| 257 | ITmfStateInterval interval = new TmfStateInterval(start, t, i, val); |
| 258 | currentStateInfo.set(i, interval); |
| 259 | } |
| 260 | } catch (AttributeNotFoundException e) { |
| 261 | /* Should not happen, we iterate over existing values. */ |
| 262 | e.printStackTrace(); |
| 263 | } |
| 264 | |
| 265 | fPartialSS.releaseQueryLock(); |
| 266 | } |
| 267 | |
| 268 | /** |
| 269 | * Single queries are not supported in partial histories. To get the same |
| 270 | * result you can do a full query, then call fullState.get(attribute). |
| 271 | */ |
| 272 | @Override |
| 273 | public ITmfStateInterval doSingularQuery(long t, int attributeQuark) { |
| 274 | throw new UnsupportedOperationException(); |
| 275 | } |
| 276 | |
| 277 | private boolean checkValidTime(long t) { |
| 278 | return (t >= getStartTime() && t <= getEndTime()); |
| 279 | } |
| 280 | |
| 281 | @Override |
| 282 | public void debugPrint(PrintWriter writer) { |
| 283 | // TODO Auto-generated method stub |
| 284 | } |
| 285 | |
| 286 | private void waitForCheckpoints() { |
| 287 | try { |
| 288 | fCheckpointsReady.await(); |
| 289 | } catch (InterruptedException e) { |
| 290 | e.printStackTrace(); |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | // ------------------------------------------------------------------------ |
| 295 | // Event requests types |
| 296 | // ------------------------------------------------------------------------ |
| 297 | |
| 298 | private class CheckpointsRequest extends TmfEventRequest { |
| 299 | private final ITmfTrace trace; |
| 300 | private final Map<Long, Long> checkpts; |
| 301 | private long eventCount; |
| 302 | private long lastCheckpointAt; |
| 303 | |
| 304 | public CheckpointsRequest(ITmfStateProvider input, Map<Long, Long> checkpoints) { |
| 305 | super(ITmfEvent.class, |
| 306 | TmfTimeRange.ETERNITY, |
| 307 | 0, |
| 308 | ITmfEventRequest.ALL_DATA, |
| 309 | ITmfEventRequest.ExecutionType.FOREGROUND); |
| 310 | checkpoints.clear(); |
| 311 | this.trace = input.getTrace(); |
| 312 | this.checkpts = checkpoints; |
| 313 | eventCount = 0; |
| 314 | lastCheckpointAt = 0; |
| 315 | |
| 316 | /* Insert a checkpoint at the start of the trace */ |
| 317 | checkpoints.put(input.getStartTime(), 0L); |
| 318 | } |
| 319 | |
| 320 | @Override |
| 321 | public void handleData(final ITmfEvent event) { |
| 322 | super.handleData(event); |
| 323 | if (event.getTrace() == trace) { |
| 324 | eventCount++; |
| 325 | |
| 326 | /* Check if we need to register a new checkpoint */ |
| 327 | if (eventCount >= lastCheckpointAt + fGranularity) { |
| 328 | checkpts.put(event.getTimestamp().getValue(), eventCount); |
| 329 | lastCheckpointAt = eventCount; |
| 330 | } |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | @Override |
| 335 | public void handleCompleted() { |
| 336 | super.handleCompleted(); |
| 337 | fCheckpointsReady.countDown(); |
| 338 | } |
| 339 | } |
| 340 | |
| 341 | private class PartialStateSystemRequest extends TmfEventRequest { |
| 342 | private final ITmfStateProvider sci; |
| 343 | private final ITmfTrace trace; |
| 344 | |
| 345 | PartialStateSystemRequest(ITmfStateProvider sci, TmfTimeRange range) { |
| 346 | super(ITmfEvent.class, |
| 347 | range, |
| 348 | 0, |
| 349 | ITmfEventRequest.ALL_DATA, |
| 350 | ITmfEventRequest.ExecutionType.BACKGROUND); |
| 351 | this.sci = sci; |
| 352 | this.trace = sci.getTrace(); |
| 353 | } |
| 354 | |
| 355 | @Override |
| 356 | public void handleData(final ITmfEvent event) { |
| 357 | super.handleData(event); |
| 358 | if (event.getTrace() == trace) { |
| 359 | sci.processEvent(event); |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | @Override |
| 364 | public void handleCompleted() { |
| 365 | /* |
| 366 | * If we're using a threaded state provider, we need to make sure |
| 367 | * all events have been handled by the state system before doing |
| 368 | * queries on it. |
| 369 | */ |
| 370 | if (fPartialInput instanceof AbstractTmfStateProvider) { |
| 371 | ((AbstractTmfStateProvider) fPartialInput).waitForEmptyQueue(); |
| 372 | } |
| 373 | super.handleCompleted(); |
| 374 | } |
| 375 | |
| 376 | } |
| 377 | } |