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提交 5ac45917 authored 作者: andrei's avatar andrei
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Use DecisionMakers for transactional update/lock/commit/rollback

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h2/src/main/org/h2/command/Command.java
浏览文件 @ 5ac45917
......@@ -7,6 +7,8 @@ package org.h2.command;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
import org.h2.api.ErrorCode;
import org.h2.engine.Constants;
import org.h2.engine.Database;
......@@ -184,7 +186,7 @@ public abstract class Command implements CommandInterface {
startTimeNanos = 0;
long start = 0;
Database database = session.getDatabase();
Object sync = database.isMultiThreaded() ? (Object) session : (Object) database;
Object sync = database.getMvStore() != null ? null : database.isMultiThreaded() ? session : database;
session.waitIfExclusiveModeEnabled();
boolean callStop = true;
boolean writing = !isReadOnly();
......@@ -193,13 +195,21 @@ public abstract class Command implements CommandInterface {
// wait
}
}
synchronized (sync) {
session.startStatementWithinTransaction();
session.setCurrentCommand(this, false);
try {
while (true) {
database.checkPowerOff();
try {
ResultInterface result = query(maxrows);
ResultInterface result;
if (sync != null) {
//noinspection SynchronizationOnLocalVariableOrMethodParameter
synchronized (sync) {
result = query(maxrows);
}
} else {
result = query(maxrows);
}
callStop = !result.isLazy();
return result;
} catch (DbException e) {
......@@ -236,13 +246,12 @@ public abstract class Command implements CommandInterface {
}
}
}
}
@Override
public ResultWithGeneratedKeys executeUpdate(Object generatedKeysRequest) {
long start = 0;
Database database = session.getDatabase();
Object sync = database.isMultiThreaded() ? (Object) session : (Object) database;
Object sync = database.getMvStore() != null ? null : database.isMultiThreaded() ? session : database;
session.waitIfExclusiveModeEnabled();
boolean callStop = true;
boolean writing = !isReadOnly();
......@@ -251,14 +260,22 @@ public abstract class Command implements CommandInterface {
// wait
}
}
synchronized (sync) {
Session.Savepoint rollback = session.setSavepoint();
session.startStatementWithinTransaction();
session.setCurrentCommand(this, generatedKeysRequest);
try {
while (true) {
database.checkPowerOff();
try {
int updateCount = update();
int updateCount;
if (sync != null) {
//noinspection SynchronizationOnLocalVariableOrMethodParameter
synchronized (sync) {
updateCount = update();
}
} else {
updateCount = update();
}
if (!Boolean.FALSE.equals(generatedKeysRequest)) {
return new ResultWithGeneratedKeys.WithKeys(updateCount,
session.getGeneratedKeys().getKeys(session));
......@@ -302,7 +319,6 @@ public abstract class Command implements CommandInterface {
}
}
}
}
private long filterConcurrentUpdate(DbException e, long start) {
int errorCode = e.getErrorCode();
......@@ -311,26 +327,9 @@ public abstract class Command implements CommandInterface {
errorCode != ErrorCode.ROW_NOT_FOUND_WHEN_DELETING_1) {
throw e;
}
long now = System.nanoTime() / 1_000_000;
if (start != 0 && now - start > session.getLockTimeout()) {
throw DbException.get(ErrorCode.LOCK_TIMEOUT_1, e.getCause(), "");
}
Database database = session.getDatabase();
int sleep = 1 + MathUtils.randomInt(10);
while (true) {
try {
if (database.isMultiThreaded()) {
Thread.sleep(sleep);
} else {
database.wait(sleep);
}
} catch (InterruptedException e1) {
// ignore
}
long slept = System.nanoTime() / 1_000_000 - now;
if (slept >= sleep) {
break;
}
long now = System.nanoTime();
if (start != 0 && now - start > TimeUnit.MILLISECONDS.toNanos(session.getLockTimeout())) {
throw DbException.get(ErrorCode.LOCK_TIMEOUT_1, e);
}
return start == 0 ? now : start;
}
......
h2/src/main/org/h2/engine/Database.java
浏览文件 @ 5ac45917
......@@ -331,6 +331,12 @@ public class Database implements DataHandler {
}
}
public long getLockTimeout() {
Setting setting = findSetting(
SetTypes.getTypeName(SetTypes.DEFAULT_LOCK_TIMEOUT));
return setting == null ? Constants.INITIAL_LOCK_TIMEOUT : setting.getIntValue();
}
/**
* Create a new row for a table.
*
......
h2/src/main/org/h2/engine/Session.java
浏览文件 @ 5ac45917
......@@ -64,6 +64,8 @@ import org.h2.value.ValueString;
*/
public class Session extends SessionWithState implements TransactionStore.RollbackListener {
public enum State { INIT, RUNNING, BLOCKED, SLEEP, CLOSED }
/**
* This special log position means that the log entry has been written.
*/
......@@ -158,6 +160,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
private ArrayList<Value> temporaryLobs;
private Transaction transaction;
private State state = State.INIT;
private long startStatement = -1;
public Session(Database database, User user, int id) {
......@@ -167,10 +170,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
this.undoLog = new UndoLog(this);
this.user = user;
this.id = id;
Setting setting = database.findSetting(
SetTypes.getTypeName(SetTypes.DEFAULT_LOCK_TIMEOUT));
this.lockTimeout = setting == null ?
Constants.INITIAL_LOCK_TIMEOUT : setting.getIntValue();
this.lockTimeout = (int)database.getLockTimeout();
this.currentSchemaName = Constants.SCHEMA_MAIN;
this.columnNamerConfiguration = ColumnNamerConfiguration.getDefault();
}
......@@ -861,6 +861,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
@Override
public void close() {
if (!closed) {
state = State.CLOSED;
try {
database.checkPowerOff();
......@@ -874,9 +875,9 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
// and we need to unlock before we call removeSession(), which might
// want to take the meta lock using the system session.
database.unlockMeta(this);
database.removeSession(this);
} finally {
closed = true;
database.removeSession(this);
}
}
}
......@@ -1212,11 +1213,15 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
if (lastThrottle + TimeUnit.MILLISECONDS.toNanos(Constants.THROTTLE_DELAY) > time) {
return;
}
State prevState = this.state;
lastThrottle = time + throttleNs;
try {
this.state = State.SLEEP;
Thread.sleep(TimeUnit.NANOSECONDS.toMillis(throttleNs));
} catch (Exception e) {
// ignore InterruptedException
} finally {
this.state = prevState;
}
}
......@@ -1244,6 +1249,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
long now = System.nanoTime();
cancelAtNs = now + TimeUnit.MILLISECONDS.toNanos(queryTimeout);
}
state = command == null ? State.SLEEP : State.RUNNING;
}
/**
......@@ -1633,7 +1639,7 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
public Value getTransactionId() {
if (database.getMvStore() != null) {
if (transaction == null) {
if (transaction == null || !transaction.hasChanges()) {
return ValueNull.INSTANCE;
}
return ValueString.get(Long.toString(getTransaction().getSequenceNum()));
......@@ -1674,14 +1680,14 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
database.shutdownImmediately();
throw DbException.get(ErrorCode.DATABASE_IS_CLOSED);
}
transaction = store.getTransactionStore().begin(this);
transaction = store.getTransactionStore().begin(this, this.lockTimeout, id);
}
startStatement = -1;
}
return transaction;
}
public long getStatementSavepoint() {
private long getStatementSavepoint() {
if (startStatement == -1) {
startStatement = getTransaction().setSavepoint();
}
......@@ -1754,6 +1760,18 @@ public class Session extends SessionWithState implements TransactionStore.Rollba
tablesToAnalyze.add(table);
}
public State getState() {
return getBlockingSessionId() != 0 ? State.BLOCKED : state;
}
public void setState(State state) {
this.state = state;
}
public int getBlockingSessionId() {
return transaction == null ? 0 : transaction.getBlockerId();
}
@Override
public void onRollback(MVMap<Object, VersionedValue> map, Object key,
VersionedValue existingValue,
......
h2/src/main/org/h2/mvstore/DataUtils.java
浏览文件 @ 5ac45917
......@@ -101,6 +101,11 @@ public final class DataUtils {
*/
public static final int ERROR_TRANSACTION_TOO_BIG = 104;
/**
* Deadlock discovered and one of transactions involved chosen as victim and rolled back.
*/
public static final int ERROR_TRANSACTIONS_DEADLOCK = 105;
/**
* The type for leaf page.
*/
......
h2/src/main/org/h2/mvstore/MVMap.java
浏览文件 @ 5ac45917
......@@ -1382,7 +1382,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
}
}
public enum Decision { ABORT, REMOVE, PUT }
public enum Decision { ABORT, REMOVE, PUT, REPEAT }
/**
* Class DecisionMaker provides callback interface (and should become a such in Java 8)
......@@ -1520,6 +1520,9 @@ public class MVMap<K, V> extends AbstractMap<K, V>
boolean needUnlock = false;
try {
switch (decision) {
case REPEAT:
decisionMaker.reset();
continue;
case ABORT:
if(rootReference != getRoot()) {
decisionMaker.reset();
......@@ -1528,6 +1531,10 @@ public class MVMap<K, V> extends AbstractMap<K, V>
return result;
case REMOVE: {
if (index < 0) {
if(rootReference != getRoot()) {
decisionMaker.reset();
continue;
}
return null;
}
if (attempt > 2 && !(needUnlock = lockRoot(decisionMaker, rootReference,
......
h2/src/main/org/h2/mvstore/db/MVPrimaryIndex.java
浏览文件 @ 5ac45917
......@@ -115,12 +115,18 @@ public class MVPrimaryIndex extends BaseIndex {
TransactionMap<Value, Value> map = getMap(session);
Value key = ValueLong.get(row.getKey());
try {
if (map.put(key, ValueArray.get(row.getValueList())) != null) {
Value oldValue = map.putIfAbsent(key, ValueArray.get(row.getValueList()));
if (oldValue != null) {
String sql = "PRIMARY KEY ON " + table.getSQL();
if (mainIndexColumn >= 0 && mainIndexColumn < indexColumns.length) {
sql += "(" + indexColumns[mainIndexColumn].getSQL() + ")";
}
DbException e = DbException.get(ErrorCode.DUPLICATE_KEY_1, sql);
int errorCode = ErrorCode.CONCURRENT_UPDATE_1;
if (map.get(key) != null) {
// committed
errorCode = ErrorCode.DUPLICATE_KEY_1;
}
DbException e = DbException.get(errorCode, sql + " " + oldValue);
e.setSource(this);
throw e;
}
......@@ -156,6 +162,19 @@ public class MVPrimaryIndex extends BaseIndex {
}
}
public void lockRows(Session session, Iterator<Row> rowsForUpdate) {
TransactionMap<Value, Value> map = getMap(session);
while (rowsForUpdate.hasNext()) {
Row row = rowsForUpdate.next();
long key = row.getKey();
try {
map.lock(ValueLong.get(key));
} catch (IllegalStateException ex) {
throw mvTable.convertException(ex);
}
}
}
@Override
public Cursor find(Session session, SearchRow first, SearchRow last) {
ValueLong min, max;
......@@ -410,5 +429,4 @@ public class MVPrimaryIndex extends BaseIndex {
}
}
}
h2/src/main/org/h2/mvstore/db/MVTable.java
浏览文件 @ 5ac45917
......@@ -10,6 +10,7 @@ import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;
......@@ -708,7 +709,11 @@ public class MVTable extends TableBase {
index.remove(session, row);
}
} catch (Throwable e) {
try {
t.rollbackToSavepoint(savepoint);
} catch (Throwable nested) {
e.addSuppressed(nested);
}
throw DbException.convert(e);
}
analyzeIfRequired(session);
......@@ -734,26 +739,21 @@ public class MVTable extends TableBase {
index.add(session, row);
}
} catch (Throwable e) {
try {
t.rollbackToSavepoint(savepoint);
DbException de = DbException.convert(e);
if (de.getErrorCode() == ErrorCode.DUPLICATE_KEY_1) {
for (Index index : indexes) {
if (index.getIndexType().isUnique() &&
index instanceof MultiVersionIndex) {
MultiVersionIndex mv = (MultiVersionIndex) index;
if (mv.isUncommittedFromOtherSession(session, row)) {
throw DbException.get(
ErrorCode.CONCURRENT_UPDATE_1,
index.getName());
}
}
}
} catch (Throwable nested) {
e.addSuppressed(nested);
}
throw de;
throw DbException.convert(e);
}
analyzeIfRequired(session);
}
@Override
public void lockRows(Session session, Iterator<Row> rowsForUpdate) {
primaryIndex.lockRows(session, rowsForUpdate);
}
private void analyzeIfRequired(Session session) {
synchronized (this) {
if (nextAnalyze == 0 || nextAnalyze > changesSinceAnalyze++) {
......@@ -919,12 +919,15 @@ public class MVTable extends TableBase {
* @return the database exception
*/
DbException convertException(IllegalStateException e) {
if (DataUtils.getErrorCode(e.getMessage()) ==
DataUtils.ERROR_TRANSACTION_LOCKED) {
int errorCode = DataUtils.getErrorCode(e.getMessage());
if (errorCode == DataUtils.ERROR_TRANSACTION_LOCKED) {
throw DbException.get(ErrorCode.CONCURRENT_UPDATE_1,
e, getName());
}
if (errorCode == DataUtils.ERROR_TRANSACTIONS_DEADLOCK) {
throw DbException.get(ErrorCode.DEADLOCK_1,
e, getName());
}
return store.convertIllegalStateException(e);
}
}
h2/src/main/org/h2/mvstore/db/MVTableEngine.java
浏览文件 @ 5ac45917
......@@ -165,7 +165,7 @@ public class MVTableEngine implements TableEngine {
}
this.transactionStore = new TransactionStore(
store,
new ValueDataType(db.getCompareMode(), db, null));
new ValueDataType(db.getCompareMode(), db, null), db.getLockTimeout());
// transactionStore.init();
} catch (IllegalStateException e) {
throw convertIllegalStateException(e);
......
h2/src/main/org/h2/mvstore/rtree/MVRTreeMap.java
浏览文件 @ 5ac45917
......@@ -180,6 +180,7 @@ public final class MVRTreeMap<V> extends MVMap<SpatialKey, V> {
result = index < 0 ? null : (V)p.getValue(index);
Decision decision = decisionMaker.decide(result, value);
switch (decision) {
case REPEAT: break;
case ABORT: break;
case REMOVE:
if(index >= 0) {
......
h2/src/main/org/h2/mvstore/tx/CommitDecisionMaker.java 0 → 100644
浏览文件 @ 5ac45917
/*
* Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mvstore.tx;
import org.h2.mvstore.MVMap;
/**
* Class CommitDecisionMaker makes a decision during post-commit processing
* about how to transform uncommitted map entry into committed one,
* based on undo log information.
*
* @author <a href='mailto:andrei.tokar@gmail.com'>Andrei Tokar</a>
*/
final class CommitDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
private long undoKey;
private MVMap.Decision decision;
public void setUndoKey(long undoKey) {
this.undoKey = undoKey;
reset();
}
@Override
public MVMap.Decision decide(VersionedValue existingValue, VersionedValue providedValue) {
assert decision == null;
if (existingValue == null) {
// map entry was treated as committed already and
// removed already by another commited by now transaction
decision = MVMap.Decision.ABORT;
} else {
if (existingValue.getOperationId() == undoKey) {
// this is final undo log entry for this key
if (existingValue.value == null) {
decision = MVMap.Decision.REMOVE;
} else {
decision = MVMap.Decision.PUT;
}
} else {
// this is not a final undo log entry for this key,
// or map entry was treated as committed already and
// overwritten already by another transaction
// see TxDecisionMaker.decide()
decision = MVMap.Decision.ABORT;
}
}
return decision;
}
@SuppressWarnings("unchecked")
@Override
public VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
assert decision == MVMap.Decision.PUT;
assert existingValue != null;
return new VersionedValue(0L, existingValue.value);
}
@Override
public void reset() {
decision = null;
}
@Override
public String toString() {
return "commit " + TransactionStore.getTransactionId(undoKey);
}
}
h2/src/main/org/h2/mvstore/tx/RollbackDecisionMaker.java 0 → 100644
浏览文件 @ 5ac45917
/*
* Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mvstore.tx;
import org.h2.mvstore.MVMap;
/**
* Class RollbackDecisionMaker process undo log record during transaction rollback.
*
* @author <a href='mailto:andrei.tokar@gmail.com'>Andrei Tokar</a>
*/
final class RollbackDecisionMaker extends MVMap.DecisionMaker<Object[]> {
private final TransactionStore store;
private final long transactionId;
private final long toLogId;
private final TransactionStore.RollbackListener listener;
private MVMap.Decision decision;
RollbackDecisionMaker(TransactionStore store, long transactionId, long toLogId,
TransactionStore.RollbackListener listener) {
this.store = store;
this.transactionId = transactionId;
this.toLogId = toLogId;
this.listener = listener;
}
@Override
public MVMap.Decision decide(Object[] existingValue, Object[] providedValue) {
assert decision == null;
assert existingValue != null;
/*
if (existingValue == null) {
// this should only be possible during initialization
// when previously database was abruptly killed
// assert !store.isInitialized();
decision = MVMap.Decision.ABORT;
} else {
*/
VersionedValue valueToRestore = (VersionedValue) existingValue[2];
long operationId;
if (valueToRestore == null ||
(operationId = valueToRestore.getOperationId()) == 0 ||
TransactionStore.getTransactionId(operationId) == transactionId
&& TransactionStore.getLogId(operationId) < toLogId) {
int mapId = (Integer) existingValue[0];
MVMap<Object, VersionedValue> map = store.openMap(mapId);
if (map != null && !map.isClosed()) {
Object key = existingValue[1];
VersionedValue previousValue = map.operate(key, valueToRestore, MVMap.DecisionMaker.DEFAULT);
listener.onRollback(map, key, previousValue, valueToRestore);
}
}
decision = MVMap.Decision.REMOVE;
// }
return decision;
}
@Override
public void reset() {
decision = null;
}
@Override
public String toString() {
return "rollback-" + transactionId;
}
}
h2/src/main/org/h2/mvstore/tx/Transaction.java
浏览文件 @ 5ac45917
......@@ -106,19 +106,60 @@ public class Transaction {
*/
private final AtomicLong statusAndLogId;
/**
* Reference to a counter for an earliest store version used by this transaction.
* Referenced version and all newer ones can not be discarded
* at least until this transaction ends.
*/
private MVStore.TxCounter txCounter;
/**
* Transaction name.
*/
private String name;
/**
* Indicates whether this transaction was stored in preparedTransactions map
*/
boolean wasStored;
/**
* How long to wait for blocking transaction to commit or rollback.
*/
final long timeoutMillis;
/**
* Identification of the owner of this transaction,
* usually the owner is a database session.
*/
private final int ownerId;
/**
* Blocking transaction, if any
*/
private volatile Transaction blockingTransaction;
/**
* Map on which this transaction is blocked.
*/
MVMap blockingMap;
/**
* Key in blockingMap on which this transaction is blocked.
*/
Object blockingKey;
Transaction(TransactionStore store, int transactionId, long sequenceNum, int status,
String name, long logId, TransactionStore.RollbackListener listener) {
String name, long logId, long timeoutMillis, int ownerId,
TransactionStore.RollbackListener listener) {
this.store = store;
this.transactionId = transactionId;
this.sequenceNum = sequenceNum;
this.statusAndLogId = new AtomicLong(composeState(status, logId, false));
this.name = name;
this.timeoutMillis = timeoutMillis;
this.ownerId = ownerId;
this.listener = listener;
}
......@@ -201,6 +242,10 @@ public class Transaction {
return name;
}
public int getBlockerId() {
return blockingTransaction == null ? 0 : blockingTransaction.ownerId;
}
/**
* Create a new savepoint.
*
......@@ -217,8 +262,8 @@ public class Transaction {
public void markStatementEnd() {
MVStore.TxCounter counter = txCounter;
txCounter = null;
if(counter != null) {
txCounter = null;
store.store.deregisterVersionUsage(counter);
}
}
......@@ -322,9 +367,9 @@ public class Transaction {
boolean hasChanges = false;
try {
long state = setStatus(STATUS_COMMITTING);
long logId = getLogId(state);
hasChanges = hasChanges(state);
if (hasChanges) {
long logId = getLogId(state);
store.commit(this, logId);
}
} catch (Throwable e) {
......@@ -364,6 +409,7 @@ public class Transaction {
"while rollback to savepoint was in progress",
transactionId);
}
notifyAllWaitingTransactions();
}
}
......@@ -420,6 +466,70 @@ public class Transaction {
}
}
void closeIt() {
long lastState = setStatus(STATUS_CLOSED);
store.store.deregisterVersionUsage(txCounter);
if(hasChanges(lastState) || hasRollback(lastState)) {
notifyAllWaitingTransactions();
}
}
private synchronized void notifyAllWaitingTransactions() {
notifyAll();
}
public boolean waitFor(Transaction toWaitFor) {
if (isDeadlocked(toWaitFor)) {
StringBuilder details = new StringBuilder(String.format("Transaction %d has been chosen as a deadlock victim. Details:%n", transactionId));
for(Transaction tx = toWaitFor, nextTx; (nextTx = tx.blockingTransaction) != null; tx = nextTx) {
details.append(String.format("Transaction %d attempts to update map <%s> entry with key <%s> modified by transaction %s%n",
tx.transactionId, tx.blockingMap.getName(), tx.blockingKey, tx.blockingTransaction));
if (nextTx == this) {
details.append(String.format("Transaction %d attempts to update map <%s> entry with key <%s> modified by transaction %s%n",
transactionId, blockingMap.getName(), blockingKey, toWaitFor));
throw DataUtils.newIllegalStateException(DataUtils.ERROR_TRANSACTIONS_DEADLOCK, details.toString());
}
}
}
blockingTransaction = toWaitFor;
try {
return toWaitFor.waitForThisToEnd(timeoutMillis);
} finally {
blockingMap = null;
blockingKey = null;
blockingTransaction = null;
}
}
private boolean isDeadlocked(Transaction toWaitFor) {
for(Transaction tx = toWaitFor, nextTx;
(nextTx = tx.blockingTransaction) != null && tx.getStatus() == Transaction.STATUS_OPEN;
tx = nextTx) {
if (nextTx == this) {
return true;
}
}
return false;
}
private synchronized boolean waitForThisToEnd(long millis) {
long until = System.currentTimeMillis() + millis;
int status;
while((status = getStatus()) != STATUS_CLOSED && status != STATUS_ROLLING_BACK) {
long dur = until - System.currentTimeMillis();
if(dur <= 0) {
return false;
}
try {
wait(dur);
} catch (InterruptedException ex) {
return false;
}
}
return true;
}
/**
* Remove the map.
*
......
h2/src/main/org/h2/mvstore/tx/TransactionMap.java
浏览文件 @ 5ac45917
......@@ -181,7 +181,7 @@ public class TransactionMap<K, V> {
* @throws IllegalStateException if a lock timeout occurs
*/
public V remove(K key) {
return set(key, null);
return set(key, (V)null);
}
/**
......@@ -200,6 +200,36 @@ public class TransactionMap<K, V> {
return set(key, value);
}
/**
* Put the value for the given key if entry for this key does not exist.
* It is atomic equivalent of the following expression:
* contains(key) ? get(k) : put(key, value);
*
* @param key the key
* @param value the new value (not null)
* @return the old value
*/
public V putIfAbsent(K key, V value) {
DataUtils.checkArgument(value != null, "The value may not be null");
TxDecisionMaker decisionMaker = new TxDecisionMaker.PutIfAbsentDecisionMaker(map.getId(), key, value, transaction);
return set(key, decisionMaker);
}
/**
* Lock row for the given key.
* <p>
* If the row is locked, this method will retry until the row could be
* updated or until a lock timeout.
*
* @param key the key
* @return the locked value
* @throws IllegalStateException if a lock timeout occurs
*/
public V lock(K key) {
TxDecisionMaker decisionMaker = new TxDecisionMaker.LockDecisionMaker(map.getId(), key, transaction);
return set(key, decisionMaker);
}
/**
* Update the value for the given key, without adding an undo log entry.
*
......@@ -216,14 +246,39 @@ public class TransactionMap<K, V> {
}
private V set(K key, V value) {
transaction.checkNotClosed();
V old = get(key);
boolean ok = trySet(key, value, false);
if (ok) {
return old;
TxDecisionMaker decisionMaker = new TxDecisionMaker.PutDecisionMaker(map.getId(), key, value, transaction);
return set(key, decisionMaker);
}
private V set(K key, TxDecisionMaker decisionMaker) {
TransactionStore store = transaction.store;
Transaction blockingTransaction;
long sequenceNumWhenStarted;
VersionedValue result;
do {
sequenceNumWhenStarted = store.openTransactions.get().getVersion();
assert transaction.getBlockerId() == 0;
result = map.put(key, VersionedValue.DUMMY, decisionMaker);
MVMap.Decision decision = decisionMaker.getDecision();
assert decision != null;
assert decision != MVMap.Decision.REPEAT;
blockingTransaction = decisionMaker.getBlockingTransaction();
if (decision != MVMap.Decision.ABORT || blockingTransaction == null) {
transaction.blockingMap = null;
transaction.blockingKey = null;
//noinspection unchecked
return result == null ? null : (V) result.value;
}
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_TRANSACTION_LOCKED, "Entry is locked");
decisionMaker.reset();
transaction.blockingMap = map;
transaction.blockingKey = key;
} while (blockingTransaction.sequenceNum > sequenceNumWhenStarted || transaction.waitFor(blockingTransaction));
throw DataUtils.newIllegalStateException(DataUtils.ERROR_TRANSACTION_LOCKED,
"Map entry <{0}> with key <{1}> and value {2} is locked by tx {3} and can not be updated by tx {4} within allocated time interval {5} ms.",
map.getName(), key, result, blockingTransaction.transactionId, transaction.transactionId, transaction.timeoutMillis);
}
/**
......@@ -302,54 +357,17 @@ public class TransactionMap<K, V> {
return false;
}
}
} else {
current = map.get(key);
}
VersionedValue newValue = new VersionedValue(
TransactionStore.getOperationId(transaction.transactionId, transaction.getLogId()),
value);
if (current == null) {
// a new value
transaction.log(mapId, key, current);
VersionedValue old = map.putIfAbsent(key, newValue);
if (old != null) {
transaction.logUndo();
return false;
}
return true;
}
long id = current.operationId;
if (id == 0) {
// committed
transaction.log(mapId, key, current);
// the transaction is committed:
// overwrite the value
if (!map.replace(key, current, newValue)) {
// somebody else was faster
transaction.logUndo();
return false;
}
try {
set(key, value);
return true;
}
int tx = TransactionStore.getTransactionId(current.operationId);
if (tx == transaction.transactionId) {
// added or updated by this transaction
transaction.log(mapId, key, current);
if (!map.replace(key, current, newValue)) {
// strange, somebody overwrote the value
// even though the change was not committed
transaction.logUndo();
} catch (IllegalStateException e) {
return false;
}
return true;
}
// the transaction is not yet committed
return false;
}
/**
* Get the value for the given key at the time when this map was opened.
* Get the effective value for the given key.
*
* @param key the key
* @return the value or null
......@@ -666,7 +684,7 @@ public class TransactionMap<K, V> {
@Override
public void remove() {
throw DataUtils.newUnsupportedOperationException(
"Removing is not supported");
"Removal is not supported");
}
};
}
......@@ -776,7 +794,7 @@ public class TransactionMap<K, V> {
@Override
public final void remove() {
throw DataUtils.newUnsupportedOperationException(
"Removing is not supported");
"Removal is not supported");
}
}
}
h2/src/main/org/h2/mvstore/tx/TransactionStore.java
浏览文件 @ 5ac45917
......@@ -31,6 +31,11 @@ public class TransactionStore {
*/
final MVStore store;
/**
* Default blocked transaction timeout
*/
private final long timeoutMillis;
/**
* The persisted map of prepared transactions.
* Key: transactionId, value: [ status, name ].
......@@ -115,7 +120,7 @@ public class TransactionStore {
* @param store the store
*/
public TransactionStore(MVStore store) {
this(store, new ObjectDataType());
this(store, new ObjectDataType(), 0);
}
/**
......@@ -123,10 +128,12 @@ public class TransactionStore {
*
* @param store the store
* @param dataType the data type for map keys and values
* @param timeoutMillis lock aquisition timeout in milliseconds, 0 means no wait
*/
public TransactionStore(MVStore store, DataType dataType) {
public TransactionStore(MVStore store, DataType dataType, long timeoutMillis) {
this.store = store;
this.dataType = dataType;
this.timeoutMillis = timeoutMillis;
preparedTransactions = store.openMap("openTransactions",
new MVMap.Builder<Integer, Object[]>());
DataType oldValueType = new VersionedValue.Type(dataType);
......@@ -188,7 +195,7 @@ public class TransactionStore {
assert lastUndoKey != null;
assert getTransactionId(lastUndoKey) == transactionId;
long logId = getLogId(lastUndoKey) + 1;
registerTransaction(transactionId, status, name, logId, listener);
registerTransaction(transactionId, status, name, logId, timeoutMillis, 0, listener);
key = undoLog.ceilingKey(nextTxUndoKey);
}
}
......@@ -247,7 +254,7 @@ public class TransactionStore {
* @param operationId the operation id
* @return the transaction id
*/
static int getTransactionId(long operationId) {
public static int getTransactionId(long operationId) {
return (int) (operationId >>> LOG_ID_BITS);
}
......@@ -302,23 +309,28 @@ public class TransactionStore {
* @return the transaction
*/
public Transaction begin() {
return begin(RollbackListener.NONE);
return begin(RollbackListener.NONE, timeoutMillis, 0);
}
/**
* Begin a new transaction.
* @param listener to be notified in case of a rollback
*
* @param timeoutMillis to wait for a blocking transaction
* @param ownerId of the owner (Session?) to be reported by getBlockerId
* @return the transaction
*/
public Transaction begin(RollbackListener listener) {
Transaction transaction = registerTransaction(0, Transaction.STATUS_OPEN, null, 0, listener);
public Transaction begin(RollbackListener listener, long timeoutMillis, int ownerId) {
if(timeoutMillis <= 0) {
timeoutMillis = this.timeoutMillis;
}
Transaction transaction = registerTransaction(0, Transaction.STATUS_OPEN, null, 0,
timeoutMillis, ownerId, listener);
return transaction;
}
private Transaction registerTransaction(int txId, int status, String name, long logId,
RollbackListener listener) {
long timeoutMillis, int ownerId, RollbackListener listener) {
int transactionId;
long sequenceNo;
boolean success;
......@@ -343,7 +355,8 @@ public class TransactionStore {
success = openTransactions.compareAndSet(original, clone);
} while(!success);
Transaction transaction = new Transaction(this, transactionId, sequenceNo, status, name, logId, listener);
Transaction transaction = new Transaction(this, transactionId, sequenceNo, status, name, logId,
timeoutMillis, ownerId, listener);
assert transactions.get(transactionId) == null;
transactions.set(transactionId, transaction);
......@@ -441,6 +454,7 @@ public class TransactionStore {
// made by this transaction, to be considered as "committed"
flipCommittingTransactionsBit(transactionId, true);
CommitDecisionMaker commitDecisionMaker = new CommitDecisionMaker();
// TODO could synchronize on blocks (100 at a time or so)
rwLock.writeLock().lock();
try {
......@@ -461,18 +475,8 @@ public class TransactionStore {
MVMap<Object, VersionedValue> map = openMap(mapId);
if (map != null) { // might be null if map was removed later
Object key = op[1];
VersionedValue value = map.get(key);
if (value != null) {
// only commit (remove/update) value if we've reached
// last undoLog entry for a given key
if (value.operationId == undoKey) {
if (value.value == null) {
map.remove(key);
} else {
map.put(key, new VersionedValue(0L, value.value));
}
}
}
commitDecisionMaker.setUndoKey(undoKey);
map.operate(key, null, commitDecisionMaker);
}
undoLog.remove(undoKey);
}
......@@ -576,11 +580,13 @@ public class TransactionStore {
* and amount of unsaved changes is sizable.
*
* @param t the transaction
* @param hasChanges false for R/O tx
* @param hasChanges true if transaction has done any updated
* (even if fully rolled back),
* false if just data access
*/
synchronized void endTransaction(Transaction t, boolean hasChanges) {
t.closeIt();
int txId = t.transactionId;
t.setStatus(Transaction.STATUS_CLOSED);
assert transactions.get(txId) == t : transactions.get(txId) + " != " + t;
transactions.set(txId, null);
......@@ -632,35 +638,12 @@ public class TransactionStore {
// TODO could synchronize on blocks (100 at a time or so)
rwLock.writeLock().lock();
try {
int transactionId = t.getId();
RollbackDecisionMaker decisionMaker = new RollbackDecisionMaker(this, transactionId, toLogId, t.listener);
for (long logId = maxLogId - 1; logId >= toLogId; logId--) {
Long undoKey = getOperationId(t.getId(), logId);
Object[] op = undoLog.get(undoKey);
if (op == null) {
// partially rolled back: load previous
undoKey = undoLog.floorKey(undoKey);
if (undoKey == null ||
getTransactionId(undoKey) != t.getId()) {
break;
}
logId = getLogId(undoKey) + 1;
continue;
}
int mapId = ((Integer) op[0]).intValue();
MVMap<Object, VersionedValue> map = openMap(mapId);
if (map != null) {
Object key = op[1];
VersionedValue oldValue = (VersionedValue) op[2];
VersionedValue currentValue;
if (oldValue == null) {
// this transaction added the value
currentValue = map.remove(key);
} else {
// this transaction updated the value
currentValue = map.put(key, oldValue);
}
t.listener.onRollback(map, key, currentValue, oldValue);
}
undoLog.remove(undoKey);
Long undoKey = getOperationId(transactionId, logId);
undoLog.operate(undoKey, null, decisionMaker);
decisionMaker.reset();
}
} finally {
rwLock.writeLock().unlock();
......@@ -886,5 +869,4 @@ public class TransactionStore {
}
}
}
h2/src/main/org/h2/mvstore/tx/TxDecisionMaker.java 0 → 100644
浏览文件 @ 5ac45917
/*
* Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mvstore.tx;
import org.h2.mvstore.MVMap;
import static org.h2.mvstore.tx.TransactionStore.getTransactionId;
/**
* Class TxDecisionMaker.
*
* @author <a href='mailto:andrei.tokar@gmail.com'>Andrei Tokar</a>
*/
public abstract class TxDecisionMaker extends MVMap.DecisionMaker<VersionedValue> {
private final int mapId;
private final Object key;
final Object value;
private final Transaction transaction;
long undoKey;
private Transaction blockingTransaction;
private MVMap.Decision decision;
TxDecisionMaker(int mapId, Object key, Object value, Transaction transaction) {
this.mapId = mapId;
this.key = key;
this.value = value;
this.transaction = transaction;
}
@Override
public MVMap.Decision decide(VersionedValue existingValue, VersionedValue providedValue) {
assert decision == null;
assert providedValue != null;
long id;
int blockingId;
// if map does not have that entry yet
if (existingValue == null ||
// or entry is a committed one
(id = existingValue.getOperationId()) == 0 ||
// or it came from the same transaction
isThisTransaction(blockingId = getTransactionId(id))) {
logIt(existingValue);
decision = MVMap.Decision.PUT;
} else if (isCommitted(blockingId)) {
// Condition above means that entry belongs to a committing transaction.
// We assume that we are looking at the final value for this transaction,
// and if it's not the case, then it will fail later,
// because a tree root has definitely been changed.
logIt(existingValue.value == null ? null : new VersionedValue(0L, existingValue.value));
decision = MVMap.Decision.PUT;
} else if(fetchTransaction(blockingId) == null) {
// condition above means transaction has been committed/rplled back and closed by now
return setDecision(MVMap.Decision.REPEAT);
} else {
// this entry comes from a different transaction, and this transaction is not committed yet
// should wait on blockingTransaction that was determined earlier
decision = MVMap.Decision.ABORT;
}
return decision;
}
@Override
public final void reset() {
if (decision != null && decision != MVMap.Decision.ABORT && decision != MVMap.Decision.REPEAT) {
// positive decision has been made already and undo record created,
// but map was updated afterwards and undo record deletion required
transaction.logUndo();
}
blockingTransaction = null;
decision = null;
}
public final MVMap.Decision getDecision() {
return decision;
}
final Transaction getBlockingTransaction() {
return blockingTransaction;
}
final void logIt(VersionedValue value) {
undoKey = transaction.log(mapId, key, value);
}
final boolean isThisTransaction(int transactionId) {
return transactionId == transaction.transactionId;
}
final boolean isCommitted(int transactionId) {
return transaction.store.committingTransactions.get().get(transactionId);
}
final Transaction fetchTransaction(int transactionId) {
return (blockingTransaction = transaction.store.getTransaction(transactionId));
}
final MVMap.Decision setDecision(MVMap.Decision d) {
return decision = d;
}
@Override
public final String toString() {
return "txdm " + transaction.transactionId;
}
public static class PutDecisionMaker extends TxDecisionMaker
{
PutDecisionMaker(int mapId, Object key, Object value, Transaction transaction) {
super(mapId, key, value, transaction);
}
@SuppressWarnings("unchecked")
@Override
public final VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
return new VersionedValue(undoKey, value);
}
}
public static final class PutIfAbsentDecisionMaker extends PutDecisionMaker
{
PutIfAbsentDecisionMaker(int mapId, Object key, Object value, Transaction transaction) {
super(mapId, key, value, transaction);
}
@Override
public MVMap.Decision decide(VersionedValue existingValue, VersionedValue providedValue) {
assert getDecision() == null;
assert providedValue != null;
int blockingId;
// if map does not have that entry yet
if (existingValue == null) {
logIt(null);
return setDecision(MVMap.Decision.PUT);
} else {
long id = existingValue.getOperationId();
if (id == 0 // entry is a committed one
// or it came from the same transaction
|| isThisTransaction(blockingId = getTransactionId(id))) {
if(existingValue.value != null) {
return setDecision(MVMap.Decision.ABORT);
}
logIt(existingValue);
return setDecision(MVMap.Decision.PUT);
} else if (isCommitted(blockingId) && existingValue.value == null) {
// entry belongs to a committing transaction
// and therefore will be committed soon
logIt(null);
return setDecision(MVMap.Decision.PUT);
} else if(fetchTransaction(blockingId) == null) {
// map already has specified key from uncommitted
// at the time transaction, which is closed by now
// we can retry right away
return setDecision(MVMap.Decision.REPEAT);
} else {
// map already has specified key from uncommitted transaction
// we need to wait for it to close and then try again
return setDecision(MVMap.Decision.ABORT);
}
}
}
}
public static final class LockDecisionMaker extends TxDecisionMaker
{
LockDecisionMaker(int mapId, Object key, Transaction transaction) {
super(mapId, key, null, transaction);
}
@SuppressWarnings("unchecked")
@Override
public VersionedValue selectValue(VersionedValue existingValue, VersionedValue providedValue) {
return new VersionedValue(undoKey, existingValue == null ? null : existingValue.value);
}
}
}
h2/src/main/org/h2/mvstore/tx/VersionedValue.java
浏览文件 @ 5ac45917
......@@ -16,6 +16,8 @@ import java.nio.ByteBuffer;
*/
public class VersionedValue {
public static final VersionedValue DUMMY = new VersionedValue(0L, new Object());
/**
* The operation id.
*/
......
h2/src/main/org/h2/table/Table.java
浏览文件 @ 5ac45917
......@@ -511,7 +511,7 @@ public abstract class Table extends SchemaObjectBase {
try {
removeRow(session, o);
} catch (DbException e) {
if (e.getErrorCode() == ErrorCode.CONCURRENT_UPDATE_1) {
if (e.getErrorCode() == ErrorCode.CONCURRENT_UPDATE_1 || e.getErrorCode() == ErrorCode.ROW_NOT_FOUND_WHEN_DELETING_1) {
session.rollbackTo(rollback, false);
session.startStatementWithinTransaction();
rollback = session.setSavepoint();
......
h2/src/test/org/h2/test/TestBase.java
浏览文件 @ 5ac45917
......@@ -151,7 +151,7 @@ public abstract class TestBase {
}
} catch (Throwable e) {
println("FAIL " + e.toString());
logError("FAIL " + e.toString(), e);
logError("FAIL ("+conf+") " + e.toString(), e);
if (config.stopOnError) {
throw new AssertionError("ERROR");
}
......
h2/src/test/org/h2/test/mvcc/TestMvcc4.java
浏览文件 @ 5ac45917
......@@ -11,7 +11,6 @@ import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Timestamp;
import java.util.Map;
import java.util.concurrent.CountDownLatch;
import org.h2.test.TestBase;
......@@ -42,7 +41,8 @@ public class TestMvcc4 extends TestBase {
}
private void testSelectForUpdateAndUpdateConcurrency() throws SQLException {
Connection setup = getConnection("mvcc4");
deleteDb("mvcc4");
Connection setup = getConnection("mvcc4;MULTI_THREADED=TRUE");
setup.setAutoCommit(false);
{
......@@ -82,7 +82,13 @@ public class TestMvcc4 extends TestBase {
ps.executeQuery().next();
executedUpdate.countDown();
waitForThreadToBlockOnDB(mainThread);
// interrogate new "blocker_id" metatable field instead of
// relying on stacktraces!? to determine when session is blocking
PreparedStatement stmt = c2.prepareStatement("SELECT * FROM INFORMATION_SCHEMA.SESSIONS WHERE BLOCKER_ID = SESSION_ID()");
ResultSet resultSet;
do {
resultSet = stmt.executeQuery();
} while(!resultSet.next());
c2.commit();
c2.close();
......@@ -103,7 +109,7 @@ public class TestMvcc4 extends TestBase {
// for lock case.
PreparedStatement ps = c1.prepareStatement("UPDATE test SET lastUpdated = ?");
ps.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
ps.executeUpdate();
assertEquals(2, ps.executeUpdate());
c1.commit();
c1.close();
......@@ -114,44 +120,12 @@ public class TestMvcc4 extends TestBase {
ps = verify.prepareStatement("SELECT COUNT(*) FROM test");
ResultSet rs = ps.executeQuery();
assertTrue(rs.next());
assertTrue(rs.getInt(1) == 2);
assertEquals(2,rs.getInt(1));
verify.commit();
verify.close();
setup.close();
}
/**
* Wait for the given thread to block on synchronizing on the database
* object.
*
* @param t the thread
*/
void waitForThreadToBlockOnDB(Thread t) {
while (true) {
// sleep the first time through the loop so we give the main thread
// a chance
try {
Thread.sleep(20);
} catch (InterruptedException e1) {
// ignore
}
// TODO must not use getAllStackTraces, as the method names are
// implementation details
Map<Thread, StackTraceElement[]> threadMap = Thread.getAllStackTraces();
StackTraceElement[] elements = threadMap.get(t);
if (elements != null
&&
elements.length > 1 &&
(config.multiThreaded ? "sleep".equals(elements[0]
.getMethodName()) : "wait".equals(elements[0]
.getMethodName())) &&
"filterConcurrentUpdate"
.equals(elements[1].getMethodName())) {
return;
}
}
}
}
......
h2/src/test/org/h2/test/mvcc/TestMvccMultiThreaded.java
浏览文件 @ 5ac45917
......@@ -7,11 +7,11 @@ package org.h2.test.mvcc;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.CyclicBarrier;
import org.h2.api.ErrorCode;
import org.h2.test.TestAll;
import org.h2.test.TestBase;
import org.h2.util.Task;
......@@ -36,12 +36,9 @@ public class TestMvccMultiThreaded extends TestBase {
}
testConcurrentSelectForUpdate();
testMergeWithUniqueKeyViolation();
// not supported currently
if (!config.multiThreaded) {
testConcurrentMerge();
testConcurrentUpdate();
}
}
private void testConcurrentSelectForUpdate() throws Exception {
deleteDb(getTestName());
......@@ -55,22 +52,12 @@ public class TestMvccMultiThreaded extends TestBase {
Task task = new Task() {
@Override
public void call() throws Exception {
Connection conn = getConnection(getTestName());
try (Connection conn = getConnection(getTestName())) {
Statement stat = conn.createStatement();
try {
while (!stop) {
try {
stat.execute("select * from test where id=1 for update");
} catch (SQLException e) {
int errorCode = e.getErrorCode();
assertTrue(e.getMessage(),
errorCode == ErrorCode.DEADLOCK_1 ||
errorCode == ErrorCode.LOCK_TIMEOUT_1);
}
}
} finally {
conn.close();
}
}
}.execute();
tasks.add(task);
......@@ -113,7 +100,6 @@ public class TestMvccMultiThreaded extends TestBase {
conn.createStatement().execute(
"create table test(id int primary key, name varchar)");
Task[] tasks = new Task[len];
final boolean[] stop = { false };
for (int i = 0; i < len; i++) {
final Connection c = connList[i];
c.setAutoCommit(false);
......@@ -124,14 +110,12 @@ public class TestMvccMultiThreaded extends TestBase {
c.createStatement().execute(
"merge into test values(1, 'x')");
c.commit();
Thread.sleep(1);
}
}
};
tasks[i].execute();
}
Thread.sleep(1000);
stop[0] = true;
for (int i = 0; i < len; i++) {
tasks[i].get();
}
......@@ -157,18 +141,24 @@ public class TestMvccMultiThreaded extends TestBase {
final int count = 1000;
Task[] tasks = new Task[len];
final CountDownLatch latch = new CountDownLatch(len);
final CyclicBarrier barrier = new CyclicBarrier(len);
for (int i = 0; i < len; i++) {
final int x = i;
// Recent changes exposed a race condition in this test itself.
// Without preliminary record locking, counter will be off.
connList[x].setAutoCommit(false);
tasks[i] = new Task() {
@Override
public void call() throws Exception {
for (int a = 0; a < count; a++) {
ResultSet rs = connList[x].createStatement().executeQuery(
"select value from test for update");
assertTrue(rs.next());
connList[x].createStatement().execute(
"update test set value=value+1");
latch.countDown();
latch.await();
connList[x].commit();
barrier.await();
}
}
};
......
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