HDFS-7915. The DataNode can sometimes allocate a ShortCircuitShm slot and fail to tell the DFSClient about it because of a network error (cmccabe)

This commit is contained in:
Colin Patrick Mccabe 2015-03-13 18:29:49 -07:00
parent 6fdef76cc3
commit 5aa892ed48
10 changed files with 178 additions and 43 deletions

View File

@ -1177,6 +1177,9 @@ Release 2.7.0 - UNRELEASED
HDFS-7722. DataNode#checkDiskError should also remove Storage when error
is found. (Lei Xu via Colin P. McCabe)
HDFS-7915. The DataNode can sometimes allocate a ShortCircuitShm slot and
fail to tell the DFSClient about it because of a network error (cmccabe)
Release 2.6.1 - UNRELEASED
INCOMPATIBLE CHANGES

View File

@ -17,6 +17,8 @@
*/
package org.apache.hadoop.hdfs;
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitFdResponse.USE_RECEIPT_VERIFICATION;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
@ -69,12 +71,23 @@
public class BlockReaderFactory implements ShortCircuitReplicaCreator {
static final Log LOG = LogFactory.getLog(BlockReaderFactory.class);
public static class FailureInjector {
public void injectRequestFileDescriptorsFailure() throws IOException {
// do nothing
}
}
@VisibleForTesting
static ShortCircuitReplicaCreator
createShortCircuitReplicaInfoCallback = null;
private final DFSClient.Conf conf;
/**
* Injects failures into specific operations during unit tests.
*/
private final FailureInjector failureInjector;
/**
* The file name, for logging and debugging purposes.
*/
@ -169,6 +182,7 @@ public class BlockReaderFactory implements ShortCircuitReplicaCreator {
public BlockReaderFactory(DFSClient.Conf conf) {
this.conf = conf;
this.failureInjector = conf.brfFailureInjector;
this.remainingCacheTries = conf.nCachedConnRetry;
}
@ -518,11 +532,12 @@ private ShortCircuitReplicaInfo requestFileDescriptors(DomainPeer peer,
final DataOutputStream out =
new DataOutputStream(new BufferedOutputStream(peer.getOutputStream()));
SlotId slotId = slot == null ? null : slot.getSlotId();
new Sender(out).requestShortCircuitFds(block, token, slotId, 1);
new Sender(out).requestShortCircuitFds(block, token, slotId, 1, true);
DataInputStream in = new DataInputStream(peer.getInputStream());
BlockOpResponseProto resp = BlockOpResponseProto.parseFrom(
PBHelper.vintPrefixed(in));
DomainSocket sock = peer.getDomainSocket();
failureInjector.injectRequestFileDescriptorsFailure();
switch (resp.getStatus()) {
case SUCCESS:
byte buf[] = new byte[1];
@ -532,8 +547,13 @@ private ShortCircuitReplicaInfo requestFileDescriptors(DomainPeer peer,
try {
ExtendedBlockId key =
new ExtendedBlockId(block.getBlockId(), block.getBlockPoolId());
if (buf[0] == USE_RECEIPT_VERIFICATION.getNumber()) {
LOG.trace("Sending receipt verification byte for slot " + slot);
sock.getOutputStream().write(0);
}
replica = new ShortCircuitReplica(key, fis[0], fis[1], cache,
Time.monotonicNow(), slot);
return new ShortCircuitReplicaInfo(replica);
} catch (IOException e) {
// This indicates an error reading from disk, or a format error. Since
// it's not a socket communication problem, we return null rather than
@ -545,7 +565,6 @@ private ShortCircuitReplicaInfo requestFileDescriptors(DomainPeer peer,
IOUtils.cleanup(DFSClient.LOG, fis[0], fis[1]);
}
}
return new ShortCircuitReplicaInfo(replica);
case ERROR_UNSUPPORTED:
if (!resp.hasShortCircuitAccessVersion()) {
LOG.warn("short-circuit read access is disabled for " +

View File

@ -337,6 +337,8 @@ public static class Conf {
final long shortCircuitCacheStaleThresholdMs;
final long keyProviderCacheExpiryMs;
public BlockReaderFactory.FailureInjector brfFailureInjector =
new BlockReaderFactory.FailureInjector();
public Conf(Configuration conf) {
// The hdfsTimeout is currently the same as the ipc timeout

View File

@ -138,10 +138,13 @@ public void transferBlock(final ExtendedBlock blk,
* to use no slot id.
* @param maxVersion Maximum version of the block data the client
* can understand.
* @param supportsReceiptVerification True if the client supports
* receipt verification.
*/
public void requestShortCircuitFds(final ExtendedBlock blk,
final Token<BlockTokenIdentifier> blockToken,
SlotId slotId, int maxVersion) throws IOException;
SlotId slotId, int maxVersion, boolean supportsReceiptVerification)
throws IOException;
/**
* Release a pair of short-circuit FDs requested earlier.

View File

@ -186,7 +186,7 @@ private void opRequestShortCircuitFds(DataInputStream in) throws IOException {
try {
requestShortCircuitFds(PBHelper.convert(proto.getHeader().getBlock()),
PBHelper.convert(proto.getHeader().getToken()),
slotId, proto.getMaxVersion());
slotId, proto.getMaxVersion(), true);
} finally {
if (traceScope != null) traceScope.close();
}

View File

@ -181,7 +181,8 @@ public void transferBlock(final ExtendedBlock blk,
@Override
public void requestShortCircuitFds(final ExtendedBlock blk,
final Token<BlockTokenIdentifier> blockToken,
SlotId slotId, int maxVersion) throws IOException {
SlotId slotId, int maxVersion, boolean supportsReceiptVerification)
throws IOException {
OpRequestShortCircuitAccessProto.Builder builder =
OpRequestShortCircuitAccessProto.newBuilder()
.setHeader(DataTransferProtoUtil.buildBaseHeader(
@ -189,6 +190,7 @@ public void requestShortCircuitFds(final ExtendedBlock blk,
if (slotId != null) {
builder.setSlotId(PBHelper.convert(slotId));
}
builder.setSupportsReceiptVerification(supportsReceiptVerification);
OpRequestShortCircuitAccessProto proto = builder.build();
send(out, Op.REQUEST_SHORT_CIRCUIT_FDS, proto);
}

View File

@ -22,6 +22,8 @@
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status.ERROR_INVALID;
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status.ERROR_UNSUPPORTED;
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status.SUCCESS;
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitFdResponse.USE_RECEIPT_VERIFICATION;
import static org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitFdResponse.DO_NOT_USE_RECEIPT_VERIFICATION;
import static org.apache.hadoop.hdfs.server.datanode.DataNode.DN_CLIENTTRACE_FORMAT;
import static org.apache.hadoop.util.Time.now;
@ -291,10 +293,14 @@ public void run() {
@Override
public void requestShortCircuitFds(final ExtendedBlock blk,
final Token<BlockTokenIdentifier> token,
SlotId slotId, int maxVersion) throws IOException {
SlotId slotId, int maxVersion, boolean supportsReceiptVerification)
throws IOException {
updateCurrentThreadName("Passing file descriptors for block " + blk);
BlockOpResponseProto.Builder bld = BlockOpResponseProto.newBuilder();
FileInputStream fis[] = null;
SlotId registeredSlotId = null;
boolean success = false;
try {
try {
if (peer.getDomainSocket() == null) {
throw new IOException("You cannot pass file descriptors over " +
@ -305,14 +311,10 @@ public void requestShortCircuitFds(final ExtendedBlock blk,
isCached(blk.getBlockPoolId(), blk.getBlockId());
datanode.shortCircuitRegistry.registerSlot(
ExtendedBlockId.fromExtendedBlock(blk), slotId, isCached);
registeredSlotId = slotId;
}
try {
fis = datanode.requestShortCircuitFdsForRead(blk, token, maxVersion);
} finally {
if ((fis == null) && (slotId != null)) {
datanode.shortCircuitRegistry.unregisterSlot(slotId);
}
}
Preconditions.checkState(fis != null);
bld.setStatus(SUCCESS);
bld.setShortCircuitAccessVersion(DataNode.CURRENT_BLOCK_FORMAT_VERSION);
} catch (ShortCircuitFdsVersionException e) {
@ -329,26 +331,45 @@ public void requestShortCircuitFds(final ExtendedBlock blk,
bld.setStatus(ERROR);
bld.setMessage(e.getMessage());
}
try {
bld.build().writeDelimitedTo(socketOut);
if (fis != null) {
FileDescriptor fds[] = new FileDescriptor[fis.length];
for (int i = 0; i < fds.length; i++) {
fds[i] = fis[i].getFD();
}
byte buf[] = new byte[] { (byte)0 };
peer.getDomainSocket().
sendFileDescriptors(fds, buf, 0, buf.length);
byte buf[] = new byte[1];
if (supportsReceiptVerification) {
buf[0] = (byte)USE_RECEIPT_VERIFICATION.getNumber();
} else {
buf[0] = (byte)DO_NOT_USE_RECEIPT_VERIFICATION.getNumber();
}
DomainSocket sock = peer.getDomainSocket();
sock.sendFileDescriptors(fds, buf, 0, buf.length);
if (supportsReceiptVerification) {
LOG.trace("Reading receipt verification byte for " + slotId);
int val = sock.getInputStream().read();
if (val < 0) {
throw new EOFException();
}
} else {
LOG.trace("Receipt verification is not enabled on the DataNode. " +
"Not verifying " + slotId);
}
success = true;
}
} finally {
if ((!success) && (registeredSlotId != null)) {
LOG.info("Unregistering " + registeredSlotId + " because the " +
"requestShortCircuitFdsForRead operation failed.");
datanode.shortCircuitRegistry.unregisterSlot(registeredSlotId);
}
if (ClientTraceLog.isInfoEnabled()) {
DatanodeRegistration dnR = datanode.getDNRegistrationForBP(blk
.getBlockPoolId());
BlockSender.ClientTraceLog.info(String.format(
"src: 127.0.0.1, dest: 127.0.0.1, op: REQUEST_SHORT_CIRCUIT_FDS," +
" blockid: %s, srvID: %s, success: %b",
blk.getBlockId(), dnR.getDatanodeUuid(), (fis != null)
));
blk.getBlockId(), dnR.getDatanodeUuid(), success));
}
if (fis != null) {
IOUtils.cleanup(LOG, fis);

View File

@ -30,6 +30,7 @@
import java.util.Iterator;
import java.util.Set;
import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.io.IOUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
@ -83,7 +84,7 @@ public class ShortCircuitRegistry {
private static final int SHM_LENGTH = 8192;
private static class RegisteredShm extends ShortCircuitShm
public static class RegisteredShm extends ShortCircuitShm
implements DomainSocketWatcher.Handler {
private final String clientName;
private final ShortCircuitRegistry registry;
@ -383,4 +384,14 @@ public void shutdown() {
}
IOUtils.closeQuietly(watcher);
}
public static interface Visitor {
void accept(HashMap<ShmId, RegisteredShm> segments,
HashMultimap<ExtendedBlockId, Slot> slots);
}
@VisibleForTesting
public synchronized void visit(Visitor visitor) {
visitor.accept(segments, slots);
}
}

View File

@ -179,6 +179,12 @@ message OpRequestShortCircuitAccessProto {
* The shared memory slot to use, if we are using one.
*/
optional ShortCircuitShmSlotProto slotId = 3;
/**
* True if the client supports verifying that the file descriptor has been
* sent successfully.
*/
optional bool supportsReceiptVerification = 4 [default = false];
}
message ReleaseShortCircuitAccessRequestProto {
@ -230,6 +236,11 @@ enum Status {
IN_PROGRESS = 12;
}
enum ShortCircuitFdResponse {
DO_NOT_USE_RECEIPT_VERIFICATION = 0;
USE_RECEIPT_VERIFICATION = 1;
}
message PipelineAckProto {
required sint64 seqno = 1;
repeated uint32 reply = 2;

View File

@ -36,13 +36,16 @@
import java.util.Iterator;
import java.util.Map;
import com.google.common.collect.HashMultimap;
import org.apache.commons.lang.mutable.MutableBoolean;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.BlockReaderFactory;
import org.apache.hadoop.hdfs.BlockReaderTestUtil;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.DFSInputStream;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
@ -52,11 +55,14 @@
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader;
import org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry;
import org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry.RegisteredShm;
import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.PerDatanodeVisitorInfo;
import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.Visitor;
import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.CacheVisitor;
import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.ShortCircuitReplicaCreator;
import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.net.unix.DomainSocket;
import org.apache.hadoop.net.unix.TemporarySocketDirectory;
@ -615,4 +621,61 @@ public void visit(HashMap<DatanodeInfo,
cluster.shutdown();
sockDir.close();
}
public static class TestCleanupFailureInjector
extends BlockReaderFactory.FailureInjector {
@Override
public void injectRequestFileDescriptorsFailure() throws IOException {
throw new IOException("injected I/O error");
}
}
// Regression test for HDFS-7915
@Test(timeout=60000)
public void testDataXceiverCleansUpSlotsOnFailure() throws Exception {
BlockReaderTestUtil.enableShortCircuitShmTracing();
TemporarySocketDirectory sockDir = new TemporarySocketDirectory();
Configuration conf = createShortCircuitConf(
"testDataXceiverCleansUpSlotsOnFailure", sockDir);
conf.setLong(DFS_CLIENT_READ_SHORTCIRCUIT_STREAMS_CACHE_EXPIRY_MS_KEY,
1000000000L);
MiniDFSCluster cluster =
new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
cluster.waitActive();
DistributedFileSystem fs = cluster.getFileSystem();
final Path TEST_PATH1 = new Path("/test_file1");
final Path TEST_PATH2 = new Path("/test_file2");
final int TEST_FILE_LEN = 4096;
final int SEED = 0xFADE1;
DFSTestUtil.createFile(fs, TEST_PATH1, TEST_FILE_LEN,
(short)1, SEED);
DFSTestUtil.createFile(fs, TEST_PATH2, TEST_FILE_LEN,
(short)1, SEED);
// The first read should allocate one shared memory segment and slot.
DFSTestUtil.readFileBuffer(fs, TEST_PATH1);
// The second read should fail, and we should only have 1 segment and 1 slot
// left.
fs.getClient().getConf().brfFailureInjector =
new TestCleanupFailureInjector();
try {
DFSTestUtil.readFileBuffer(fs, TEST_PATH2);
} catch (Throwable t) {
GenericTestUtils.assertExceptionContains("TCP reads were disabled for " +
"testing, but we failed to do a non-TCP read.", t);
}
ShortCircuitRegistry registry =
cluster.getDataNodes().get(0).getShortCircuitRegistry();
registry.visit(new ShortCircuitRegistry.Visitor() {
@Override
public void accept(HashMap<ShmId, RegisteredShm> segments,
HashMultimap<ExtendedBlockId, Slot> slots) {
Assert.assertEquals(1, segments.size());
Assert.assertEquals(1, slots.size());
}
});
cluster.shutdown();
sockDir.close();
}
}