About lock

11-20 of 180Refresh
Forum
22

Pessimistic Lock Timeouts setting

Hi,   I realise that JPA2 doesn't necessarily define a standard API way for Lock Timeouts. However, there is a standardised query 'hint' that can be setup to make the underlying DB lock a record for a specific time. The hint property is: "javax.persistence.lock.timeout" I have a situation
Forum
22

locks on pure query activities

that are just doing simple queries (just selects, no update or delete ...) show locks like these (question is: why there are locks and how could we get rid of that):   log1: "qtp1523553211-271" #271 prio ... ) - waiting to lock <0x0000000202239c10> (a com.objectdb.o.LFL) at com.objectdb.o.PAG
Forum
21

Pessimestic Locking doesn't release when application unexpectedly terminates.

. Our approach to this was to use Objectdb's pessimestic locking. This seems to work, but if the owner of the current pessimestic lock abruptly quits without releasing the lock it doesn't get released.    Is there anyway the server can detect that a client (lock owner is no longer connected
Issue
21

each 1-2 days objects on some objectdb level lock/block each other

thread dump shows a page cache lock (0x00000000b6681e10) by one thread. The second thread dump ... -file-read" option. In both cases it is not a deadlock but a very short lock that is not expected ... " /> <locking version
JPA Doc
21

javax.persistence.LockModeType

Lock modes can be specified by means of passing a LockModeType argument to one of the javax.persistence.EntityManager methods that take locks ( lock, find, or refresh) or to the Query.setLockMode() or TypedQuery.setLockMode() method. Lock modes can be used to specify either optimistic or
Forum
20

"Attempt to lock a non entity object" error

and then doCancelEdit works fine. Second time I doEdit produces the error "Attempt to lock a non entity ... () { try {     session.beginTransaction();     session.lock(subjectJList.getSelectedValue ... ------------------------------------------------------------- Attempt to lock a non entity object
Forum
20

Where Does ObjectDB Block/Lock?

titled, "Sample JDO Architecture for Follow Up Questions".   Questions about blocking/locking ... blocking/locking so I might adapt to achieve better concurrency. 1) Where are locks when accessing PersistenceManager by multiple threads? 2) Does it lock at PersistenceManager.currentTransaction
Forum
20

pesimistic Lock semantic

Hi   I have tested pesimistic lock and the result was for me unexpected. In the first transaction i ... that lock could not be granted, quite nice but in that moment I wanted commit the first transaction and I also got lock exception. this the test:   public void testPesimisticLock
JPA Doc
19

JPA Exceptions

causes for RollbackException are lock failures: Exceptions can also be thrown on an attempt ... during query execution: The lock exceptions (above) may also be thrown during retrieval, if database lock has been requested for retrieved entity objects and it cannot be granted.
Manual
19

JPA Entity Fields

with optimistic locking (as explained in the Locking in JPA section in chapter 3). You can expose entity ... field is explicitly defined. Therefore, optimistic locking is supported by ObjectDB