示例#1
0
  public void close() {
    if (shuttingDown.getAndSet(true)) {
      return;
    }

    mutex.lock();
    try {
      while (backgroundCompaction != null) {
        backgroundCondition.awaitUninterruptibly();
      }
    } finally {
      mutex.unlock();
    }

    compactionExecutor.shutdown();
    try {
      compactionExecutor.awaitTermination(1, TimeUnit.DAYS);
    } catch (InterruptedException e) {
      Thread.currentThread().interrupt();
    }
    try {
      versions.destroy();
    } catch (IOException ignored) {
    }
    try {
      log.close();
    } catch (IOException ignored) {
    }
    tableCache.close();
    dbLock.release();
  }
示例#2
0
  private void makeRoomForWrite(boolean force) {
    Preconditions.checkState(mutex.isHeldByCurrentThread());

    boolean allowDelay = !force;

    while (true) {
      // todo background processing system need work
      //            if (!bg_error_.ok()) {
      //              // Yield previous error
      //              s = bg_error_;
      //              break;
      //            } else
      if (allowDelay && versions.numberOfFilesInLevel(0) > L0_SLOWDOWN_WRITES_TRIGGER) {
        // We are getting close to hitting a hard limit on the number of
        // L0 files.  Rather than delaying a single write by several
        // seconds when we hit the hard limit, start delaying each
        // individual write by 1ms to reduce latency variance.  Also,
        // this delay hands over some CPU to the compaction thread in
        // case it is sharing the same core as the writer.
        try {
          mutex.unlock();
          Thread.sleep(1);
        } catch (InterruptedException e) {
          Thread.currentThread().interrupt();
          throw new RuntimeException(e);
        } finally {
          mutex.lock();
        }

        // Do not delay a single write more than once
        allowDelay = false;
      } else if (!force && memTable.approximateMemoryUsage() <= options.writeBufferSize()) {
        // There is room in current memtable
        break;
      } else if (immutableMemTable != null) {
        // We have filled up the current memtable, but the previous
        // one is still being compacted, so we wait.
        backgroundCondition.awaitUninterruptibly();
      } else if (versions.numberOfFilesInLevel(0) >= L0_STOP_WRITES_TRIGGER) {
        // There are too many level-0 files.
        //                Log(options_.info_log, "waiting...\n");
        backgroundCondition.awaitUninterruptibly();
      } else {
        // Attempt to switch to a new memtable and trigger compaction of old
        Preconditions.checkState(versions.getPrevLogNumber() == 0);

        // close the existing log
        try {
          log.close();
        } catch (IOException e) {
          throw new RuntimeException("Unable to close log file " + log.getFile(), e);
        }

        // open a new log
        long logNumber = versions.getNextFileNumber();
        try {
          this.log =
              Logs.createLogWriter(
                  new File(databaseDir, Filename.logFileName(logNumber)), logNumber);
        } catch (IOException e) {
          throw new RuntimeException(
              "Unable to open new log file "
                  + new File(databaseDir, Filename.logFileName(logNumber)).getAbsoluteFile(),
              e);
        }

        // create a new mem table
        immutableMemTable = memTable;
        memTable = new MemTable(internalKeyComparator);

        // Do not force another compaction there is space available
        force = false;

        maybeScheduleCompaction();
      }
    }
  }