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ATK-4711 : fix dead lock when autocommit=false #3918

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Merged
PanternBao merged 1 commit into from
Jun 29, 2026
Merged

ATK-4711 : fix dead lock when autocommit=false #3918

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25 changes: 23 additions & 2 deletions src/main/java/com/actiontech/dble/backend/mysql/nio/handler/query/impl/join/JoinHandler.java
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Original file line number Diff line number Diff line change
Expand Up @@ -50,6 +50,8 @@ public class JoinHandler extends OwnThreadDMLHandler {
protected List<FieldPacket> leftFieldPackets;
protected List<FieldPacket> rightFieldPackets;
private AtomicBoolean fieldSent = new AtomicBoolean(false);
// merge loop ended; set before terminateHandlerTree so late backend rows skip putLast on a full queue
private final AtomicBoolean joinMergeFinished = new AtomicBoolean(false);
private BufferPool pool;
private RowDataComparator leftComparator;
private RowDataComparator rightComparator;
Expand Down Expand Up @@ -122,20 +124,27 @@ private Item makeOtherJoinOnItem(List<FieldPacket> rowPackets, BackendConnection
@Override
public boolean rowResponse(byte[] rowNull, RowDataPacket rowPacket, boolean isLeft, BackendConnection conn) {
LOGGER.debug("rowresponse");
if (terminate.get()) {
// return true: interrupted; do not block on putLast after merge or during terminate
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
try {
if (isLeft) {
leftLock.lock();
try {
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
addRowToDeque(rowPacket, leftFieldPackets.size(), leftQueue, leftComparator);
} finally {
leftLock.unlock();
}
} else {
rightLock.lock();
try {
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
addRowToDeque(rowPacket, rightFieldPackets.size(), rightQueue, rightComparator);
} finally {
rightLock.unlock();
Expand All @@ -151,7 +160,7 @@ public boolean rowResponse(byte[] rowNull, RowDataPacket rowPacket, boolean isLe
@Override
public void rowEofResponse(byte[] data, boolean isLeft, BackendConnection conn) {
LOGGER.debug("roweof");
if (terminate.get()) {
if (terminate.get() || joinMergeFinished.get()) {
return;
}
RowDataPacket eofRow = TERMINATED_ROW;
Expand Down Expand Up @@ -219,6 +228,9 @@ protected void ownThreadJob(Object... objects) {
rightLocal = takeFirst(rightQueue);
}
}
// stop accepting backend rows and drain queues before waiting on connections in terminateHandlerTree
joinMergeFinished.set(true);
clearJoinQueuesAfterMerge();

HandlerTool.terminateHandlerTree(this);
// for trace, when join end before all rows return ,the handler should mark as finished
Expand All @@ -243,6 +255,15 @@ protected void ownThreadJob(Object... objects) {
}
}

/**
* Clear join queues after merge. Unlocked poll first so producers blocked on a full
* deque can finish;
*/
private void clearJoinQueuesAfterMerge() {
clearDeque(leftQueue);
clearDeque(rightQueue);
}

private LocalResult takeFirst(FairLinkedBlockingDeque<LocalResult> deque) throws InterruptedException {
/**
* it must be in single thread
Expand Down
43 changes: 39 additions & 4 deletions ...main/java/com/actiontech/dble/backend/mysql/nio/handler/query/impl/join/NotInHandler.java
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Original file line number Diff line number Diff line change
Expand Up @@ -29,6 +29,7 @@
import java.util.Comparator;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.ReentrantLock;

public class NotInHandler extends OwnThreadDMLHandler {
private static final Logger LOGGER = LoggerFactory.getLogger(NotInHandler.class);
Expand All @@ -43,7 +44,12 @@ public class NotInHandler extends OwnThreadDMLHandler {
private RowDataComparator leftComparator;
private RowDataComparator rightComparator;
private AtomicBoolean fieldSent = new AtomicBoolean(false);
// merge loop ended; set before terminateHandlerTree so late backend rows skip putLast on a full queue
private final AtomicBoolean joinMergeFinished = new AtomicBoolean(false);
private String charset = "UTF-8";
// prevent multi thread rowresponse
protected ReentrantLock leftLock = new ReentrantLock();
protected ReentrantLock rightLock = new ReentrantLock();

public NotInHandler(long id, NonBlockingSession session, List<Order> leftOrder, List<Order> rightOrder) {
super(id, session);
Expand Down Expand Up @@ -88,14 +94,31 @@ public void fieldEofResponse(byte[] headerNull, List<byte[]> fieldsNull, final L
@Override
public boolean rowResponse(byte[] rowNull, RowDataPacket rowPacket, boolean isLeft, BackendConnection conn) {
LOGGER.debug("rowresponse");
if (terminate.get()) {
// return true: interrupted; do not block on putLast after merge or during terminate
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
try {
if (isLeft) {
addRowToDeque(rowPacket, leftFieldPackets.size(), leftQueue, leftComparator);
leftLock.lock();
try {
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
addRowToDeque(rowPacket, leftFieldPackets.size(), leftQueue, leftComparator);
} finally {
leftLock.unlock();
}
} else {
addRowToDeque(rowPacket, rightFieldPackets.size(), rightQueue, rightComparator);
rightLock.lock();
try {
if (terminate.get() || joinMergeFinished.get()) {
return true;
}
addRowToDeque(rowPacket, rightFieldPackets.size(), rightQueue, rightComparator);
} finally {
rightLock.unlock();
}
}
} catch (InterruptedException e) {
LOGGER.info("not in row exception", e);
Expand All @@ -107,7 +130,7 @@ public boolean rowResponse(byte[] rowNull, RowDataPacket rowPacket, boolean isLe
@Override
public void rowEofResponse(byte[] data, boolean isLeft, BackendConnection conn) {
LOGGER.info("roweof");
if (terminate.get()) {
if (terminate.get() || joinMergeFinished.get()) {
return;
}
RowDataPacket eofRow = TERMINATED_ROW;
Expand Down Expand Up @@ -164,6 +187,9 @@ protected void ownThreadJob(Object... objects) {
rightLocal = takeFirst(rightQueue);
}
}
// stop accepting backend rows and drain queues before waiting on connections in terminateHandlerTree
joinMergeFinished.set(true);
clearJoinQueuesAfterMerge();
session.setHandlerEnd(this);
nextHandler.rowEofResponse(null, isLeft, conn);
HandlerTool.terminateHandlerTree(this);
Expand All @@ -179,6 +205,15 @@ protected void ownThreadJob(Object... objects) {
}
}

/**
* Clear join queues after merge. Unlocked poll first so producers blocked on a full
* deque can finish;
*/
private void clearJoinQueuesAfterMerge() {
clearDeque(leftQueue);
clearDeque(rightQueue);
}

private LocalResult takeFirst(FairLinkedBlockingDeque<LocalResult> deque) throws InterruptedException {
deque.waitUtilCount(1);
LocalResult result = deque.peekFirst();
Expand Down
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