/** Do the real work of dumpLockTableInternal. */
void dumpLockTableInternal(StatGroup tableStats, int i, boolean clear) {
StatGroup oneTable = new StatGroup("Single lock table", "Temporary stat group");
IntStat totalLocks = new IntStat(oneTable, LOCK_TOTAL);
IntStat waiters = new IntStat(oneTable, LOCK_WAITERS);
IntStat owners = new IntStat(oneTable, LOCK_OWNERS);
IntStat readLocks = new IntStat(oneTable, LOCK_READ_LOCKS);
IntStat writeLocks = new IntStat(oneTable, LOCK_WRITE_LOCKS);
Map<Long, Lock> lockTable = lockTables[i];
totalLocks.add(lockTable.size());
for (Lock lock : lockTable.values()) {
waiters.add(lock.nWaiters());
owners.add(lock.nOwners());
/* Go through all the owners for a lock. */
for (LockInfo info : lock.getOwnersClone()) {
if (info.getLockType().isWriteLock()) {
writeLocks.increment();
} else {
readLocks.increment();
}
}
}
tableStats.addAll(oneTable);
}
private StringBuilder findDeadlock1(Set<Locker> ownerSet, Lock lock, Locker rootLocker) {
Iterator<LockInfo> ownerIter = lock.getOwnersClone().iterator();
while (ownerIter.hasNext()) {
LockInfo info = ownerIter.next();
Locker locker = info.getLocker();
Lock waitsFor = locker.getWaitingFor();
if (ownerSet.contains(locker) || locker == rootLocker) {
/* Found a cycle. */
StringBuilder ret = new StringBuilder();
ret.append("Transaction ").append(locker.toString());
ret.append(" owns LockAddr:").append(System.identityHashCode(lock));
ret.append(" ").append(info).append("\n");
ret.append("Transaction ").append(locker.toString());
ret.append(" waits for");
if (waitsFor == null) {
ret.append(" nothing");
} else {
ret.append(" LockAddr:");
ret.append(System.identityHashCode(waitsFor));
}
ret.append("\n");
return ret;
}
if (waitsFor != null) {
ownerSet.add(locker);
StringBuilder sb = findDeadlock1(ownerSet, waitsFor, rootLocker);
if (sb != null) {
String waitInfo = "Transaction " + locker + " waits for " + waitsFor + "\n";
sb.insert(0, waitInfo);
return sb;
}
ownerSet.remove(locker); // is this necessary?
}
}
return null;
}
/** Do the real work of creating an lock or txn timeout message. */
LockConflictException makeTimeoutMsgInternal(
boolean isLockNotTxnTimeout,
Locker locker,
long nodeId,
LockType type,
LockGrantType grantType,
Lock useLock,
long timeout,
long start,
long now,
DatabaseImpl database) {
/*
* Because we're accessing parts of the lock, need to have protected
* access to the lock table because things can be changing out from
* underneath us. This is a big hammer to grab for so long while we
* traverse the graph, but it's only when we have a deadlock and we're
* creating a debugging message.
*
* The alternative would be to handle ConcurrentModificationExceptions
* and retry until none of them happen.
*/
if (lockTableDump) {
System.out.println("++++++++++ begin lock table dump ++++++++++");
for (int i = 0; i < nLockTables; i++) {
boolean success = false;
for (int j = 0; j < 3 && !success; j++) {
try {
StringBuilder sb = new StringBuilder();
dumpToStringNoLatch(sb, i);
System.out.println(sb.toString());
success = true;
break; // for j...
} catch (ConcurrentModificationException CME) {
continue;
}
}
if (!success) {
System.out.println("Couldn't dump locktable " + i);
}
}
System.out.println("++++++++++ end lock table dump ++++++++++");
}
StringBuilder sb = new StringBuilder();
sb.append(isLockNotTxnTimeout ? "Lock" : "Transaction");
sb.append(" expired. Locker ").append(locker);
sb.append(": waited for lock");
if (database != null) {
sb.append(" on database=").append(database.getDebugName());
}
sb.append(" LockAddr:").append(System.identityHashCode(useLock));
sb.append(" node=").append(nodeId);
sb.append(" type=").append(type);
sb.append(" grant=").append(grantType);
sb.append(" timeoutMillis=").append(timeout);
sb.append(" startTime=").append(start);
sb.append(" endTime=").append(now);
Set<LockInfo> owners = useLock.getOwnersClone();
List<LockInfo> waiters = useLock.getWaitersListClone();
sb.append("\nOwners: ").append(owners);
sb.append("\nWaiters: ").append(waiters).append("\n");
StringBuilder deadlockInfo = findDeadlock(useLock, locker);
if (deadlockInfo != null) {
sb.append(deadlockInfo);
}
LockConflictException ret =
isLockNotTxnTimeout
? newLockTimeoutException(locker, sb.toString())
: newTxnTimeoutException(locker, sb.toString());
ret.setOwnerTxnIds(getTxnIds(owners));
ret.setWaiterTxnIds(getTxnIds(waiters));
ret.setTimeoutMillis(timeout);
return ret;
}
