Example usage for org.apache.hadoop.fs FileStatus getBlockSize

List of usage examples for org.apache.hadoop.fs FileStatus getBlockSize

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In this page you can find the example usage for org.apache.hadoop.fs FileStatus getBlockSize.

Prototype

public long getBlockSize()

Source Link

Document

Get the block size of the file.

Usage

From source file:io.hops.erasure_coding.ReedSolomonDecoder.java

License:Apache License

protected int[] buildInputs(FileSystem fs, Path srcFile, FileSystem parityFs, Path parityFile,
        boolean fixSource, long errorOffset, FSDataInputStream[] inputs) throws IOException {
    LOG.info("Building inputs to recover block starting at " + errorOffset);
    try {//from   w w  w  .  j  a  va2 s  .c  om
        FileStatus srcStat = fs.getFileStatus(srcFile);
        FileStatus parityStat = fs.getFileStatus(parityFile);
        long blockSize = srcStat.getBlockSize();
        long blockIdx = (int) (errorOffset / blockSize);
        long stripeIdx;
        if (fixSource) {
            stripeIdx = blockIdx / stripeSize;
        } else {
            stripeIdx = blockIdx / paritySize;
        }

        LOG.info("FileSize = " + srcStat.getLen() + ", blockSize = " + blockSize + ", blockIdx = " + blockIdx
                + ", stripeIdx = " + stripeIdx);
        ArrayList<Integer> erasedLocations = new ArrayList<Integer>();
        // First open streams to the parity blocks.
        for (int i = 0; i < paritySize; i++) {
            long offset = blockSize * (stripeIdx * paritySize + i);
            if ((!fixSource) && offset == errorOffset) {
                LOG.info(parityFile + ":" + offset + " is known to have error, adding zeros as input " + i);
                inputs[i] = new FSDataInputStream(new RaidUtils.ZeroInputStream(offset + blockSize));
                erasedLocations.add(i);
            } else if (offset > parityStat.getLen()) {
                LOG.info(parityFile + ":" + offset + " is past file size, adding zeros as input " + i);
                inputs[i] = new FSDataInputStream(new RaidUtils.ZeroInputStream(offset + blockSize));
            } else {
                FSDataInputStream in = parityFs.open(parityFile, conf.getInt("io.file.buffer.size", 64 * 1024));
                in.seek(offset);
                LOG.info("Adding " + parityFile + ":" + offset + " as input " + i);
                inputs[i] = in;
            }
        }
        // Now open streams to the data blocks.
        for (int i = paritySize; i < paritySize + stripeSize; i++) {
            long offset = blockSize * (stripeIdx * stripeSize + i - paritySize);
            if (fixSource && offset == errorOffset) {
                LOG.info(srcFile + ":" + offset + " is known to have error, adding zeros as input " + i);
                inputs[i] = new FSDataInputStream(new RaidUtils.ZeroInputStream(offset + blockSize));
                erasedLocations.add(i);
            } else if (offset > srcStat.getLen()) {
                LOG.info(srcFile + ":" + offset + " is past file size, adding zeros as input " + i);
                inputs[i] = new FSDataInputStream(new RaidUtils.ZeroInputStream(offset + blockSize));
            } else {
                FSDataInputStream in = fs.open(srcFile, conf.getInt("io.file.buffer.size", 64 * 1024));
                in.seek(offset);
                LOG.info("Adding " + srcFile + ":" + offset + " as input " + i);
                inputs[i] = in;
            }
        }
        if (erasedLocations.size() > paritySize) {
            String msg = "Too many erased locations: " + erasedLocations.size();
            LOG.error(msg);
            throw new IOException(msg);
        }
        int[] locs = new int[erasedLocations.size()];
        for (int i = 0; i < locs.length; i++) {
            locs[i] = erasedLocations.get(i);
        }
        return locs;
    } catch (IOException e) {
        RaidUtils.closeStreams(inputs);
        throw e;
    }

}

From source file:io.hops.erasure_coding.StripeReader.java

License:Apache License

/**
 * Builds (codec.stripeLength + codec.parityLength) inputs given some erased
 * locations.//from  w w w  . j  av a2 s  .  co  m
 * Outputs:
 * - the array of input streams @param inputs
 * - the list of erased locations @param erasedLocations.
 * - the list of locations that are not read @param locationsToNotRead.
 */
public InputStream[] buildInputs(FileSystem srcFs, Path srcFile, FileStatus srcStat, FileSystem parityFs,
        Path parityFile, FileStatus parityStat, int stripeIdx, long offsetInBlock,
        List<Integer> erasedLocations, List<Integer> locationsToRead, ErasureCode code) throws IOException {
    InputStream[] inputs = new InputStream[codec.stripeLength + codec.parityLength];
    boolean redo = false;
    do {
        /*
         * In the first iteration locationsToRead is empty.
         * It is populated according to locationsToReadForDecode.
         * In consecutive iterations (if a stream failed to open)
         * the list is cleared and re-populated.
         */
        locationsToRead.clear();
        locationsToRead.addAll(code.locationsToReadForDecode(erasedLocations));

        for (int i = 0; i < inputs.length; i++) {
            boolean isErased = (erasedLocations.indexOf(i) != -1);
            boolean shouldRead = (locationsToRead.indexOf(i) != -1);
            try {
                InputStream stm = null;
                if (isErased || !shouldRead) {
                    if (isErased) {
                        LOG.info("Location " + i + " is erased, using zeros");
                    } else {
                        LOG.info("Location " + i + " need not be read, using zeros");
                    }

                    stm = new RaidUtils.ZeroInputStream(srcStat.getBlockSize()
                            * ((i < codec.parityLength) ? stripeIdx * codec.parityLength + i
                                    : stripeIdx * codec.stripeLength + i - codec.parityLength));
                } else {
                    stm = buildOneInput(i, offsetInBlock, srcFs, srcFile, srcStat, parityFs, parityFile,
                            parityStat);
                }
                inputs[i] = stm;
            } catch (IOException e) {
                if (e instanceof BlockMissingException || e instanceof ChecksumException) {
                    erasedLocations.add(i);
                    redo = true;
                    RaidUtils.closeStreams(inputs);
                    break;
                } else {
                    throw e;
                }
            }
        }
    } while (redo);
    return inputs;
}

From source file:io.hops.erasure_coding.StripeReader.java

License:Apache License

protected InputStream getParityFileInput(int locationIndex, Path parityFile, FileSystem parityFs,
        FileStatus parityStat, long offsetInBlock) throws IOException {
    // Dealing with a parity file here.
    int parityBlockIdx = (int) (codec.parityLength * stripeStartIdx + locationIndex);
    long offset = parityStat.getBlockSize() * parityBlockIdx + offsetInBlock;
    assert (offset < parityStat.getLen());
    LOG.info("Opening " + parityFile + ":" + offset + " for location " + locationIndex);
    FSDataInputStream s = parityFs.open(parityFile, conf.getInt("io.file.buffer.size", 64 * 1024));
    s.seek(offset);//from   w w w .j  av  a 2 s. com
    return s;
}

From source file:io.hops.erasure_coding.TestBlockReconstructor.java

License:Apache License

@Test
public void testSourceBlockRepair() throws IOException, InterruptedException {
    DistributedFileSystem dfs = (DistributedFileSystem) getFileSystem();
    TestDfsClient testDfsClient = new TestDfsClient(getConfig());
    testDfsClient.injectIntoDfs(dfs);//from   www  . j  a  va  2s .  c o m
    FileStatus testFileStatus = dfs.getFileStatus(testFile);

    String path = testFileStatus.getPath().toUri().getPath();
    int blockToLoose = new Random(seed)
            .nextInt((int) (testFileStatus.getLen() / testFileStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(path, 0, Long.MAX_VALUE).get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    List<LocatedBlock> lostBlocks = new ArrayList<LocatedBlock>();
    lostBlocks.add(lb);
    LocatedBlocks locatedBlocks = new LocatedBlocks(0, false, lostBlocks, null, true);
    testDfsClient.setMissingLocatedBlocks(locatedBlocks);

    LocatedBlocks missingBlocks = new LocatedBlocks(testFileStatus.getLen(), false,
            new ArrayList<LocatedBlock>(), null, true);
    missingBlocks.getLocatedBlocks().add(lb);
    BlockReconstructor blockReconstructor = new BlockReconstructor(conf);
    Decoder decoder = new Decoder(conf, Util.getCodec(Util.Codecs.SRC));
    blockReconstructor.processFile(testFile, testParityFile, missingBlocks, decoder, null);

    // Block is recovered to the same data node so no need to wait for the block report
    try {
        FSDataInputStream in = dfs.open(testFile);
        byte[] buff = new byte[TEST_BLOCK_COUNT * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading failed", e);
        fail("Repair failed. Missing a block.");
    }
}

From source file:io.hops.erasure_coding.TestBlockReconstructor.java

License:Apache License

@Test
public void testParityBlockRepair() throws IOException, InterruptedException {
    DistributedFileSystem dfs = (DistributedFileSystem) getFileSystem();
    TestDfsClient testDfsClient = new TestDfsClient(getConfig());
    testDfsClient.injectIntoDfs(dfs);/*from   w ww.j a v a 2  s . c  o m*/
    FileStatus parityFileStatus = dfs.getFileStatus(testParityFile);

    String path = parityFileStatus.getPath().toUri().getPath();
    int blockToLoose = new Random(seed)
            .nextInt((int) (parityFileStatus.getLen() / parityFileStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(path, 0, Long.MAX_VALUE).get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    List<LocatedBlock> lostBlocks = new ArrayList<LocatedBlock>();
    lostBlocks.add(lb);
    LocatedBlocks locatedBlocks = new LocatedBlocks(0, false, lostBlocks, null, true);
    testDfsClient.setMissingLocatedBlocks(locatedBlocks);

    LocatedBlocks missingBlocks = new LocatedBlocks(parityFileStatus.getLen(), false,
            new ArrayList<LocatedBlock>(), null, true);
    missingBlocks.getLocatedBlocks().add(lb);
    BlockReconstructor blockReconstructor = new BlockReconstructor(conf);
    Decoder decoder = new Decoder(conf, Util.getCodec(Util.Codecs.SRC));
    blockReconstructor.processParityFile(testFile, testParityFile, missingBlocks, decoder, null);

    // Block is recovered to the same data node so no need to wait for the block report
    try {
        FSDataInputStream in = dfs.open(testParityFile);
        byte[] buff = new byte[DFS_TEST_BLOCK_SIZE * codec.parityLength];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading failed", e);
        fail("Repair failed. Missing a block.");
    }
}

From source file:io.hops.erasure_coding.TestErasureCodingManager.java

License:Apache License

@Test
public void testSourceRepair() throws IOException, InterruptedException {
    Codec.initializeCodecs(getConfig());
    EncodingPolicy policy = new EncodingPolicy("src", (short) 1);
    Util.createRandomFile(dfs, testFile, seed, TEST_BLOCK_COUNT, DFS_TEST_BLOCK_SIZE, policy);
    FileStatus testFileStatus = dfs.getFileStatus(testFile);

    while (!dfs.getEncodingStatus(testFile.toUri().getPath()).isEncoded()) {
        try {/*from   w ww . j  a v  a2 s .  c o  m*/
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.error("Wait for encoding thread was interrupted.");
        }
    }

    Thread.sleep(2 * conf.getInt("dfs.blockreport.intervalMsec", 0));

    EncodingStatus status = dfs.getEncodingStatus(testFile.toUri().getPath());
    Path parityPath = new Path("/parity/" + status.getParityFileName());
    FileStatus parityStatus = dfs.getFileStatus(parityPath);
    assertEquals(parityStatus.getLen(), TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE);
    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading parity failed", e);
        fail("Parity could not be read.");
    }

    String path = testFileStatus.getPath().toUri().getPath();
    int blockToLoose = new Random(seed)
            .nextInt((int) (testFileStatus.getLen() / testFileStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(path, 0, Long.MAX_VALUE).get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    LOG.info("Losing block " + lb.toString());

    Thread.sleep(2 * conf.getInt("dfs.blockreport.intervalMsec", 0)
            + 2 * conf.getInt(DFSConfigKeys.RECHECK_INTERVAL_KEY, 0));

    while (true) {
        Thread.sleep(10000);
        EncodingStatus status2 = dfs.getEncodingStatus(testFile.toUri().getPath());
        LOG.info("Current status is " + status2.getStatus());
        if (status2.getStatus() == EncodingStatus.Status.ENCODED) {
            break;
        }
    }

    try {
        FSDataInputStream in = dfs.open(testFile);
        byte[] buff = new byte[TEST_BLOCK_COUNT * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        fail("Repair failed. Missing a block.");
    }
}

From source file:io.hops.erasure_coding.TestErasureCodingManager.java

License:Apache License

@Test
public void testParityRepair() throws IOException, InterruptedException {
    Codec.initializeCodecs(getConfig());
    EncodingPolicy policy = new EncodingPolicy("src", (short) 1);
    Util.createRandomFile(dfs, testFile, seed, TEST_BLOCK_COUNT, DFS_TEST_BLOCK_SIZE, policy);

    while (!dfs.getEncodingStatus(testFile.toUri().getPath()).isEncoded()) {
        try {//from  ww  w .  j a v a  2 s  . com
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.error("Wait for encoding thread was interrupted.");
        }
    }

    Thread.sleep(2 * conf.getInt("dfs.blockreport.intervalMsec", 0));

    EncodingStatus status = dfs.getEncodingStatus(testFile.toUri().getPath());
    Path parityPath = new Path(conf.get(DFSConfigKeys.PARITY_FOLDER, DFSConfigKeys.DEFAULT_PARITY_FOLDER),
            status.getParityFileName());
    FileStatus parityStatus = dfs.getFileStatus(parityPath);
    assertEquals(parityStatus.getLen(), TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE);
    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading parity failed", e);
        fail("Parity could not be read.");
    }

    int blockToLoose = new Random(seed).nextInt((int) (parityStatus.getLen() / parityStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(parityPath.toUri().getPath(), 0, Long.MAX_VALUE)
            .get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    LOG.info("Losing block " + lb.toString());

    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
        fail("Successfully read parity file which should have been broken.");
    } catch (BlockMissingException e) {
    }

    Thread.sleep(2 * conf.getInt("dfs.blockreport.intervalMsec", 0)
            + 2 * conf.getInt(DFSConfigKeys.RECHECK_INTERVAL_KEY, 0));

    while (true) {
        Thread.sleep(10000);
        EncodingStatus status2 = dfs.getEncodingStatus(testFile.toUri().getPath());
        LOG.info("Current status is " + status2);
        if (status2.getParityStatus() == EncodingStatus.ParityStatus.HEALTHY) {
            break;
        }
    }

    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        fail("Repair failed. Missing a block.");
    }
}

From source file:io.hops.erasure_coding.TestErasureCodingManagerEndless.java

License:Apache License

@Ignore
public void endlessSourceTest() throws IOException, InterruptedException {
    DistributedFileSystem dfs = (DistributedFileSystem) getFileSystem();

    Codec.initializeCodecs(getConfig());
    EncodingPolicy policy = new EncodingPolicy("src", (short) 1);
    Util.createRandomFile(dfs, testFile, seed, TEST_BLOCK_COUNT, DFS_TEST_BLOCK_SIZE, policy);
    FileStatus testFileStatus = dfs.getFileStatus(testFile);

    while (!dfs.getEncodingStatus(testFile.toUri().getPath()).isEncoded()) {
        try {/*ww  w .ja v a  2s .co  m*/
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.error("Wait for encoding thread was interrupted.");
        }
    }

    EncodingStatus status = dfs.getEncodingStatus(testFile.toUri().getPath());
    Path parityPath = new Path("/parity/" + status.getParityFileName());
    FileStatus parityStatus = dfs.getFileStatus(parityPath);
    assertEquals(parityStatus.getLen(), TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE);
    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading parity failed", e);
        fail("Parity could not be read.");
    }

    String path = testFileStatus.getPath().toUri().getPath();
    int blockToLoose = new Random(seed)
            .nextInt((int) (testFileStatus.getLen() / testFileStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(path, 0, Long.MAX_VALUE).get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    LOG.info("Loosing block " + lb.toString());

    EncodingStatus lastStatus = null;
    while (true) {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.warn("Was interrupted", e);
        }
        EncodingStatus status2 = dfs.getEncodingStatus(testFile.toUri().getPath());
        if (status2.equals(lastStatus) == false) {
            LOG.info("New status is " + status2.getStatus());
            lastStatus = status2;
        }
    }
}

From source file:io.hops.erasure_coding.TestErasureCodingManagerEndless.java

License:Apache License

@Ignore
public void endlessParityTest() throws IOException, InterruptedException {
    DistributedFileSystem dfs = (DistributedFileSystem) getFileSystem();

    Codec.initializeCodecs(getConfig());
    EncodingPolicy policy = new EncodingPolicy("src", (short) 1);
    Util.createRandomFile(dfs, testFile, seed, TEST_BLOCK_COUNT, DFS_TEST_BLOCK_SIZE, policy);
    FileStatus testFileStatus = dfs.getFileStatus(testFile);

    while (!dfs.getEncodingStatus(testFile.toUri().getPath()).isEncoded()) {
        try {/*from   ww  w  . j a v  a2  s.  co  m*/
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.error("Wait for encoding thread was interrupted.");
        }
    }

    EncodingStatus status = dfs.getEncodingStatus(testFile.toUri().getPath());
    Path parityPath = new Path("/parity/" + status.getParityFileName());
    FileStatus parityStatus = dfs.getFileStatus(parityPath);
    assertEquals(parityStatus.getLen(), TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE);
    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        LOG.error("Reading parity failed", e);
        fail("Parity could not be read.");
    }

    int blockToLoose = new Random(seed).nextInt((int) (parityStatus.getLen() / parityStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(parityPath.toUri().getPath(), 0, Long.MAX_VALUE)
            .get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    LOG.info("Loosing block " + lb.toString());

    try {
        FSDataInputStream in = dfs.open(parityPath);
        byte[] buff = new byte[TEST_STRIPE_COUNT * TEST_PARITY_LENGTH * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
        fail("Successfully read parity file which should have been broken.");
    } catch (BlockMissingException e) {
    }

    EncodingStatus lastStatus = null;
    while (true) {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            LOG.warn("Was interrupted", e);
        }
        EncodingStatus status2 = dfs.getEncodingStatus(testFile.toUri().getPath());
        if (status2.equals(lastStatus) == false) {
            LOG.info("New status is " + status2);
            lastStatus = status2;
        }
    }
}

From source file:io.hops.erasure_coding.TestMapReduceBlockRepairManager.java

License:Apache License

@Test
public void testBlockRepair() throws IOException, InterruptedException {
    DistributedFileSystem dfs = (DistributedFileSystem) getFileSystem();
    TestDfsClient testDfsClient = new TestDfsClient(getConfig());
    testDfsClient.injectIntoDfs(dfs);//from   www.  ja va2 s  .c o m

    MapReduceEncodingManager encodingManager = new MapReduceEncodingManager(conf);

    Util.createRandomFile(dfs, testFile, seed, TEST_BLOCK_COUNT, DFS_TEST_BLOCK_SIZE);
    Codec.initializeCodecs(conf);
    FileStatus testFileStatus = dfs.getFileStatus(testFile);
    EncodingPolicy policy = new EncodingPolicy("src", (short) 1);
    encodingManager.encodeFile(policy, testFile, parityFile);

    // Busy waiting until the encoding is done
    while (encodingManager.computeReports().size() > 0) {
        ;
    }

    String path = testFileStatus.getPath().toUri().getPath();
    int blockToLoose = new Random(seed)
            .nextInt((int) (testFileStatus.getLen() / testFileStatus.getBlockSize()));
    LocatedBlock lb = dfs.getClient().getLocatedBlocks(path, 0, Long.MAX_VALUE).get(blockToLoose);
    DataNodeUtil.loseBlock(getCluster(), lb);
    List<LocatedBlock> lostBlocks = new ArrayList<LocatedBlock>();
    lostBlocks.add(lb);
    LocatedBlocks locatedBlocks = new LocatedBlocks(0, false, lostBlocks, null, true);
    testDfsClient.setMissingLocatedBlocks(locatedBlocks);
    LOG.info("Loosing block " + lb.toString());
    getCluster().triggerBlockReports();

    MapReduceBlockRepairManager repairManager = new MapReduceBlockRepairManager(conf);
    repairManager.repairSourceBlocks("src", testFile, parityFile);

    while (true) {
        List<Report> reports = repairManager.computeReports();
        if (reports.size() == 0) {
            break;
        }
        LOG.info(reports.get(0).getStatus());
        System.out.println("WAIT");
        Thread.sleep(1000);
    }

    try {
        FSDataInputStream in = dfs.open(testFile);
        byte[] buff = new byte[TEST_BLOCK_COUNT * DFS_TEST_BLOCK_SIZE];
        in.readFully(0, buff);
    } catch (BlockMissingException e) {
        fail("Repair failed. Missing a block.");
    }
}