java.nio.channels.OverlappingFileLockException

> Hi, > I have 3 application modules. One module, creates the xml database, the > second/third module execute queries on the database (no updates are being > performed on the database). > > When the second and the third module try accessing the database, once > module is able to query the database while the other module ends up with the > below exception. > > org.basex.core.BaseXException: Improper use? Potential bug? Your feedback is > welcome: > Contact: basex-talk at mailman.uni-konstanz.de > Version: BaseX 7.8 beta > Java: Oracle Corporation, 1.7.0_25 > OS: Linux, amd64 > Stack Trace: > java.nio.channels.OverlappingFileLockException > at sun.nio.ch.SharedFileLockTable.checkList(FileLockTable.java:255) > at sun.nio.ch.SharedFileLockTable.add(FileLockTable.java:152) > at sun.nio.ch.FileChannelImpl.tryLock(FileChannelImpl.java:1017) > at org.basex.io.random.TableDiskAccess.lck(TableDiskAccess.java:183) > at > org.basex.io.random.TableDiskAccess.sharedLock(TableDiskAccess.java:170) > at > org.basex.io.random.TableDiskAccess.<init>(TableDiskAccess.java:83) > at org.basex.data.DiskData.init(DiskData.java:122) > at org.basex.data.DiskData.<init>(DiskData.java:92) > at org.basex.core.cmd.Open.open(Open.java:68) > at org.basex.core.cmd.Open.run(Open.java:35) > at org.basex.core.Command.run(Command.java:344) > at org.basex.core.Command.exec(Command.java:320) > at org.basex.core.Command.execute(Command.java:77) > at org.basex.core.Command.execute(Command.java:89) > > > Below are the options being set: > context.globalopts.set(GlobalOptions.GLOBALLOCK, false) ; > context.globalopts.set(GlobalOptions.PARALLEL, 1) ; //After referring to > https://github.com/BaseXdb/basex/issues/574 > > When the same exercise is being undertaken on a windows machine, the above > behavior does not occur. > > Regards > Narasimham > > _______________________________________________ > BaseX-Talk mailing list > BaseX-Talk at mailman.uni-konstanz.de > https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk >

> Hi Narashimham, > > If you haven’t see it yet, the Wiki page on transactions will give you > some insight how locking works in BaseX [1]. Do all of your modules > run in the same JVM, and have you ensured that all operations use the > same context? If yes, feel free to send us your sample code that > demonstrates the problem. > > Best, > Christian > > [1] http://docs.basex.org/wiki/Transaction_Management > ___________________________ > > 2013/10/20 EV Narasimham <evnarasimham at gmail.com>: > > Hi, > > I have 3 application modules. One module, creates the xml database, > the > > second/third module execute queries on the database (no updates are being > > performed on the database). > > > > When the second and the third module try accessing the database, once > > module is able to query the database while the other module ends up with > the > > below exception. > > > > org.basex.core.BaseXException: Improper use? Potential bug? Your > feedback is > > welcome: > > Contact: basex-talk at mailman.uni-konstanz.de > > Version: BaseX 7.8 beta > > Java: Oracle Corporation, 1.7.0_25 > > OS: Linux, amd64 > > Stack Trace: > > java.nio.channels.OverlappingFileLockException > > at > sun.nio.ch.SharedFileLockTable.checkList(FileLockTable.java:255) > > at sun.nio.ch.SharedFileLockTable.add(FileLockTable.java:152) > > at sun.nio.ch.FileChannelImpl.tryLock(FileChannelImpl.java:1017) > > at > org.basex.io.random.TableDiskAccess.lck(TableDiskAccess.java:183) > > at > > org.basex.io.random.TableDiskAccess.sharedLock(TableDiskAccess.java:170) > > at > > org.basex.io.random.TableDiskAccess.<init>(TableDiskAccess.java:83) > > at org.basex.data.DiskData.init(DiskData.java:122) > > at org.basex.data.DiskData.<init>(DiskData.java:92) > > at org.basex.core.cmd.Open.open(Open.java:68) > > at org.basex.core.cmd.Open.run(Open.java:35) > > at org.basex.core.Command.run(Command.java:344) > > at org.basex.core.Command.exec(Command.java:320) > > at org.basex.core.Command.execute(Command.java:77) > > at org.basex.core.Command.execute(Command.java:89) > > > > > > Below are the options being set: > > context.globalopts.set(GlobalOptions.GLOBALLOCK, false) ; > > context.globalopts.set(GlobalOptions.PARALLEL, 1) ; //After referring to > > https://github.com/BaseXdb/basex/issues/574 > > > > When the same exercise is being undertaken on a windows machine, the > above > > behavior does not occur. > > > > Regards > > Narasimham > > > > _______________________________________________ > > BaseX-Talk mailing list > > BaseX-Talk at mailman.uni-konstanz.de > > https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk > > >