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@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/574https://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 https://github.com/BaseXdb/basex/issues/574
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@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, oncemodule 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@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@mailman.uni-konstanz.de https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk
Hi Christian, There was an error in my implementation whereby a new context was generated when ever module(s) were loaded during application runtime.
After making suitable amendments to the code, the prob. is not to be seen.
Regards Narasimham
On Sun, Oct 20, 2013 at 10:23 PM, Christian Grün christian.gruen@gmail.comwrote:
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@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, oncemodule 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@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) atorg.basex.io.random.TableDiskAccess.lck(TableDiskAccess.java:183)
atorg.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@mailman.uni-konstanz.de https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk
basex-talk@mailman.uni-konstanz.de
-
Christian Grün -
EV Narasimham