com.sleepycat.je.txn
Class LockManager

java.lang.Object
  extended by com.sleepycat.je.txn.LockManager
All Implemented Interfaces:
EnvConfigObserver
Direct Known Subclasses:
DummyLockManager, LatchedLockManager, SyncedLockManager

public abstract class LockManager
extends Object
implements EnvConfigObserver

LockManager manages locks. Note that locks are counted as taking up part of the JE cache;


Field Summary
(package private)  Latch[] lockTableLatches
           
(package private)  int nLockTables
           
(package private) static long TOTAL_LOCKIMPL_OVERHEAD
           
(package private) static long TOTAL_THINLOCKIMPL_OVERHEAD
           
 
Constructor Summary
LockManager(EnvironmentImpl envImpl)
           
 
Method Summary
(package private) abstract  LockAttemptResult attemptLock(Long nodeId, Locker locker, LockType type, boolean nonBlockingRequest)
           
(package private)  LockAttemptResult attemptLockInternal(Long nodeId, Locker locker, LockType type, boolean nonBlockingRequest, int lockTableIndex)
           
(package private) abstract  void demote(long nodeId, Locker locker)
          Demote a lock from write to read.
(package private)  void demoteInternal(long nodeId, Locker locker, int lockTableIndex)
          Do the real work of demote.
 void dump()
          Debugging
(package private) abstract  void dumpLockTable(StatGroup tableStats, boolean clear)
          Dump the lock table to the lock stats.
(package private)  void dumpLockTableInternal(StatGroup tableStats, int i, boolean clear)
          Do the real work of dumpLockTableInternal.
 String dumpToString()
           
 void envConfigUpdate(DbConfigManager configMgr, EnvironmentMutableConfig ignore)
          Process notifications of mutable property changes.
(package private)  int getLockTableIndex(long nodeId)
           
(package private)  int getLockTableIndex(Long nodeId)
           
 Iterator<ThreadLocker> getThreadLockers(Thread thread)
          Returns an iterator over all thread lockers for the given thread, or an empty iterator if none.
(package private) abstract  Locker getWriteOwnerLocker(Long nodeId)
           
(package private)  Locker getWriteOwnerLockerInternal(Long nodeId, int lockTableIndex)
          Do the real work of getWriteOwnerLocker.
(package private) abstract  boolean isLocked(Long nodeId)
          Test the status of the lock on nodeId.
(package private)  boolean isLockedInternal(Long nodeId, int lockTableIndex)
          Do the real work of isLocked.
(package private) abstract  boolean isOwner(Long nodeId, Locker locker, LockType type)
          Return true if this locker owns this a lock of this type on given node.
(package private)  boolean isOwnerInternal(Long nodeId, Locker locker, LockType type, int lockTableIndex)
          Do the real work of isOwner.
(package private) abstract  boolean isWaiter(Long nodeId, Locker locker)
          Return true if this locker is waiting on this lock.
(package private)  boolean isWaiterInternal(Long nodeId, Locker locker, int lockTableIndex)
          Do the real work of isWaiter.
 StatGroup loadStats(StatsConfig config)
           
 LockGrantType lock(long nodeId, Locker locker, LockType type, long timeout, boolean nonBlockingRequest, DatabaseImpl database)
          Attempt to acquire a lock of type on nodeId.
 LockStats lockStat(StatsConfig config)
          Statistics
(package private) abstract  Lock lookupLock(Long nodeId)
           
(package private)  Lock lookupLockInternal(Long nodeId, int lockTableIndex)
           
(package private) abstract  LockConflictException makeTimeoutMsg(boolean isLockNotTxnTimeout, Locker locker, long nodeId, LockType type, LockGrantType grantType, Lock useLock, long timeout, long start, long now, DatabaseImpl database)
          Create a informative lock or txn timeout message.
(package private)  LockConflictException makeTimeoutMsgInternal(boolean isLockNotTxnTimeout, Locker locker, long nodeId, LockType type, LockGrantType grantType, Lock useLock, long timeout, long start, long now, DatabaseImpl database)
          Do the real work of creating an lock or txn timeout message.
(package private)  LockConflictException newLockNotAvailableException(Locker locker, String msg)
          This method should always be called instead of explicitly creating LockNotAvailableException, to ensure that je.lock.oldLockExceptions is enforced.
(package private) abstract  int nOwners(Long nodeId)
          Return the number of owners of this lock.
(package private)  int nOwnersInternal(Long nodeId, int lockTableIndex)
          Do the real work of nWaiters.
(package private) abstract  int nWaiters(Long nodeId)
          Return the number of waiters for this lock.
(package private)  int nWaitersInternal(Long nodeId, int lockTableIndex)
          Do the real work of nWaiters.
 void registerThreadLocker(ThreadLocker locker)
          Called when a ThreadLocker is created.
 boolean release(long nodeId, Locker locker)
          Release a lock and possibly notify any waiters that they have been granted the lock.
(package private) abstract  Set<Locker> releaseAndFindNotifyTargets(long nodeId, Locker locker)
          Release the lock, and return the set of new owners to notify, if any.
(package private)  Set<Locker> releaseAndFindNotifyTargetsInternal(long nodeId, Locker locker, int lockTableIndex)
          Do the real work of releaseAndFindNotifyTargets
(package private) static void setLockTableDump(boolean enable)
          Called when the je.txn.dumpLocks property is changed.
protected abstract  LockAttemptResult stealLock(Long nodeId, Locker locker, LockType lockType, MemoryBudget mb)
           
protected  LockAttemptResult stealLockInternal(Long nodeId, Locker locker, LockType lockType, MemoryBudget mb, int lockTableIndex)
           
(package private) abstract  void transfer(long nodeId, Locker owningLocker, Locker destLocker, boolean demoteToRead)
          Transfer ownership a lock from one locker to another locker.
(package private)  void transferInternal(long nodeId, Locker owningLocker, Locker destLocker, boolean demoteToRead, int lockTableIndex)
          Do the real work of transfer
(package private) abstract  void transferMultiple(long nodeId, Locker owningLocker, Locker[] destLockers)
          Transfer ownership a lock from one locker to a set of other txns, cloning the lock as necessary.
(package private)  void transferMultipleInternal(long nodeId, Locker owningLocker, Locker[] destLockers, int lockTableIndex)
          Do the real work of transferMultiple
 void unregisterThreadLocker(ThreadLocker locker)
          Called when a ThreadLocker is closed.
(package private) abstract  boolean validateOwnership(Long nodeId, Locker locker, LockType type, boolean flushFromWaiters, MemoryBudget mb)
           
(package private)  boolean validateOwnershipInternal(Long nodeId, Locker locker, LockType type, boolean flushFromWaiters, MemoryBudget mb, int lockTableIndex)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

TOTAL_LOCKIMPL_OVERHEAD

static final long TOTAL_LOCKIMPL_OVERHEAD

TOTAL_THINLOCKIMPL_OVERHEAD

static final long TOTAL_THINLOCKIMPL_OVERHEAD

nLockTables

int nLockTables

lockTableLatches

Latch[] lockTableLatches
Constructor Detail

LockManager

public LockManager(EnvironmentImpl envImpl)
Method Detail

envConfigUpdate

public void envConfigUpdate(DbConfigManager configMgr,
                            EnvironmentMutableConfig ignore)
Process notifications of mutable property changes.

Specified by:
envConfigUpdate in interface EnvConfigObserver

setLockTableDump

static void setLockTableDump(boolean enable)
Called when the je.txn.dumpLocks property is changed.


getLockTableIndex

int getLockTableIndex(Long nodeId)

getLockTableIndex

int getLockTableIndex(long nodeId)

lock

public LockGrantType lock(long nodeId,
                          Locker locker,
                          LockType type,
                          long timeout,
                          boolean nonBlockingRequest,
                          DatabaseImpl database)
                   throws LockConflictException,
                          DatabaseException
Attempt to acquire a lock of type on nodeId. If the lock acquisition would result in a deadlock, throw an exception.
If the requested lock is not currently available, block until it is or until timeout milliseconds have elapsed.
If a lock of type is already held, return EXISTING.
If a WRITE lock is held and a READ lock is requested, return PROMOTION.
If a lock request is for a lock that is not currently held, return either NEW or DENIED depending on whether the lock is granted or not.

Parameters:
nodeId - The NodeId to lock.
locker - The Locker to lock this on behalf of.
type - The lock type requested.
timeout - milliseconds to time out after if lock couldn't be obtained. 0 means block indefinitely. Not used if nonBlockingRequest is true.
nonBlockingRequest - if true, means don't block if lock can't be acquired, and ignore the timeout parameter.
Returns:
a LockGrantType indicating whether the request was fulfilled or not. LockGrantType.NEW means the lock grant was fulfilled and the caller did not previously hold the lock. PROMOTION means the lock was granted and it was a promotion from READ to WRITE. EXISTING means the lock was already granted (not a promotion). DENIED means the lock was not granted because the timeout passed without acquiring the lock or timeout was 0 and the lock was not immediately available.
Throws:
LockConflictException - if lock could not be acquired.
IllegalArgumentException - via db/cursor read/write methods, if non-transactional access to a replicated environment is attempted, and read-uncommitted is not specified.
DatabaseException

lookupLock

abstract Lock lookupLock(Long nodeId)
                  throws DatabaseException
Throws:
DatabaseException

lookupLockInternal

Lock lookupLockInternal(Long nodeId,
                        int lockTableIndex)

attemptLock

abstract LockAttemptResult attemptLock(Long nodeId,
                                       Locker locker,
                                       LockType type,
                                       boolean nonBlockingRequest)
                                throws DatabaseException
Throws:
DatabaseException

attemptLockInternal

LockAttemptResult attemptLockInternal(Long nodeId,
                                      Locker locker,
                                      LockType type,
                                      boolean nonBlockingRequest,
                                      int lockTableIndex)
                                throws DatabaseException
Throws:
DatabaseException

makeTimeoutMsg

abstract LockConflictException makeTimeoutMsg(boolean isLockNotTxnTimeout,
                                              Locker locker,
                                              long nodeId,
                                              LockType type,
                                              LockGrantType grantType,
                                              Lock useLock,
                                              long timeout,
                                              long start,
                                              long now,
                                              DatabaseImpl database)
                                       throws DatabaseException
Create a informative lock or txn timeout message.

Throws:
DatabaseException

makeTimeoutMsgInternal

LockConflictException makeTimeoutMsgInternal(boolean isLockNotTxnTimeout,
                                             Locker locker,
                                             long nodeId,
                                             LockType type,
                                             LockGrantType grantType,
                                             Lock useLock,
                                             long timeout,
                                             long start,
                                             long now,
                                             DatabaseImpl database)
Do the real work of creating an lock or txn timeout message.


newLockNotAvailableException

LockConflictException newLockNotAvailableException(Locker locker,
                                                   String msg)
This method should always be called instead of explicitly creating LockNotAvailableException, to ensure that je.lock.oldLockExceptions is enforced.


release

public boolean release(long nodeId,
                       Locker locker)
                throws DatabaseException
Release a lock and possibly notify any waiters that they have been granted the lock.

Parameters:
nodeId - The node ID of the lock to release.
Returns:
true if the lock is released successfully, false if the lock is not currently being held.
Throws:
DatabaseException

releaseAndFindNotifyTargets

abstract Set<Locker> releaseAndFindNotifyTargets(long nodeId,
                                                 Locker locker)
                                          throws DatabaseException
Release the lock, and return the set of new owners to notify, if any.

Returns:
null if the lock does not exist or the given locker was not the owner, a non-empty set if owners should be notified after releasing, an empty set if no notification is required.
Throws:
DatabaseException

releaseAndFindNotifyTargetsInternal

Set<Locker> releaseAndFindNotifyTargetsInternal(long nodeId,
                                                Locker locker,
                                                int lockTableIndex)
Do the real work of releaseAndFindNotifyTargets


transfer

abstract void transfer(long nodeId,
                       Locker owningLocker,
                       Locker destLocker,
                       boolean demoteToRead)
                throws DatabaseException
Transfer ownership a lock from one locker to another locker. We're not sending any notification to the waiters on the lock table, and the past and present owner should be ready for the transfer.

Throws:
DatabaseException

transferInternal

void transferInternal(long nodeId,
                      Locker owningLocker,
                      Locker destLocker,
                      boolean demoteToRead,
                      int lockTableIndex)
                throws DatabaseException
Do the real work of transfer

Throws:
DatabaseException

transferMultiple

abstract void transferMultiple(long nodeId,
                               Locker owningLocker,
                               Locker[] destLockers)
                        throws DatabaseException
Transfer ownership a lock from one locker to a set of other txns, cloning the lock as necessary. This will always be demoted to read, as we can't have multiple locker owners any other way. We're not sending any notification to the waiters on the lock table, and the past and present owners should be ready for the transfer.

Throws:
DatabaseException

transferMultipleInternal

void transferMultipleInternal(long nodeId,
                              Locker owningLocker,
                              Locker[] destLockers,
                              int lockTableIndex)
                        throws DatabaseException
Do the real work of transferMultiple

Throws:
DatabaseException

demote

abstract void demote(long nodeId,
                     Locker locker)
              throws DatabaseException
Demote a lock from write to read. Call back to the owning locker to move this to its read collection.

Parameters:
lock - The lock to release. If null, use nodeId to find lock
locker -
Throws:
DatabaseException

demoteInternal

void demoteInternal(long nodeId,
                    Locker locker,
                    int lockTableIndex)
Do the real work of demote.


isLocked

abstract boolean isLocked(Long nodeId)
                   throws DatabaseException
Test the status of the lock on nodeId. If any transaction holds any lock on it, true is returned. If no transaction holds a lock on it, false is returned. This method is only used by unit tests.

Parameters:
nodeId - The NodeId to check.
Returns:
true if any transaction holds any lock on the nodeid. false if no lock is held by any transaction.
Throws:
DatabaseException

isLockedInternal

boolean isLockedInternal(Long nodeId,
                         int lockTableIndex)
Do the real work of isLocked.


isOwner

abstract boolean isOwner(Long nodeId,
                         Locker locker,
                         LockType type)
                  throws DatabaseException
Return true if this locker owns this a lock of this type on given node. This method is only used by unit tests.

Throws:
DatabaseException

isOwnerInternal

boolean isOwnerInternal(Long nodeId,
                        Locker locker,
                        LockType type,
                        int lockTableIndex)
Do the real work of isOwner.


isWaiter

abstract boolean isWaiter(Long nodeId,
                          Locker locker)
                   throws DatabaseException
Return true if this locker is waiting on this lock. This method is only used by unit tests.

Throws:
DatabaseException

isWaiterInternal

boolean isWaiterInternal(Long nodeId,
                         Locker locker,
                         int lockTableIndex)
Do the real work of isWaiter.


nWaiters

abstract int nWaiters(Long nodeId)
               throws DatabaseException
Return the number of waiters for this lock.

Throws:
DatabaseException

nWaitersInternal

int nWaitersInternal(Long nodeId,
                     int lockTableIndex)
Do the real work of nWaiters.


nOwners

abstract int nOwners(Long nodeId)
              throws DatabaseException
Return the number of owners of this lock.

Throws:
DatabaseException

nOwnersInternal

int nOwnersInternal(Long nodeId,
                    int lockTableIndex)
Do the real work of nWaiters.


getWriteOwnerLocker

abstract Locker getWriteOwnerLocker(Long nodeId)
                             throws DatabaseException
Returns:
the transaction that owns the write lock for this
Throws:
DatabaseException

getWriteOwnerLockerInternal

Locker getWriteOwnerLockerInternal(Long nodeId,
                                   int lockTableIndex)
Do the real work of getWriteOwnerLocker.


validateOwnership

abstract boolean validateOwnership(Long nodeId,
                                   Locker locker,
                                   LockType type,
                                   boolean flushFromWaiters,
                                   MemoryBudget mb)
                            throws DatabaseException
Throws:
DatabaseException

validateOwnershipInternal

boolean validateOwnershipInternal(Long nodeId,
                                  Locker locker,
                                  LockType type,
                                  boolean flushFromWaiters,
                                  MemoryBudget mb,
                                  int lockTableIndex)

stealLock

protected abstract LockAttemptResult stealLock(Long nodeId,
                                               Locker locker,
                                               LockType lockType,
                                               MemoryBudget mb)
                                        throws DatabaseException
Throws:
DatabaseException

stealLockInternal

protected LockAttemptResult stealLockInternal(Long nodeId,
                                              Locker locker,
                                              LockType lockType,
                                              MemoryBudget mb,
                                              int lockTableIndex)
                                       throws DatabaseException
Throws:
DatabaseException

registerThreadLocker

public void registerThreadLocker(ThreadLocker locker)
Called when a ThreadLocker is created.


unregisterThreadLocker

public void unregisterThreadLocker(ThreadLocker locker)
Called when a ThreadLocker is closed.


getThreadLockers

public Iterator<ThreadLocker> getThreadLockers(Thread thread)
Returns an iterator over all thread lockers for the given thread, or an empty iterator if none.


lockStat

public LockStats lockStat(StatsConfig config)
                   throws DatabaseException
Statistics

Throws:
DatabaseException

loadStats

public StatGroup loadStats(StatsConfig config)

dumpLockTable

abstract void dumpLockTable(StatGroup tableStats,
                            boolean clear)
                     throws DatabaseException
Dump the lock table to the lock stats.

Throws:
DatabaseException

dumpLockTableInternal

void dumpLockTableInternal(StatGroup tableStats,
                           int i,
                           boolean clear)
Do the real work of dumpLockTableInternal.


dump

public void dump()
          throws DatabaseException
Debugging

Throws:
DatabaseException

dumpToString

public String dumpToString()
                    throws DatabaseException
Throws:
DatabaseException


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