Scotty Allen wrote:
Hi all,
We've been having some problems with occasional rollbacks of an embedded
database when the application is shutdown and restarted. The pattern
seems to be that you shut down our application, and then restart it, and
the database is in the same state it was the time before last that you
started it up. In other words, the whole last session seems to have
been lost.
The main machine I've been seeing it on is a Mac OS X machine running
tiger 10.4, with java 1.4.2. We're running Derby 10.0.2.1, with
derby.storage.fileSyncTransactionLog set to true. However, we think we
may have seen this problem on a Win XP machine as well.
Has anyone seen anything like this? Any thoughts about how to
troubleshoot? I just found derby.infolog.append tonight, so I'll start
using that and see if I can see anything funky in the logs when it
happens (I haven't seen anything yet, but haven't always checked the log
prior to starting up, to know if the shutdown the last time was clean).
That seems strange. I dont use Mac, but have not noticed any problems
on windows/linux.. By default, on a restart( reboot), the database is
guranteed to be in a consistent state, that is you will see only the
transactions that have been committed and not result of any uncommitted
transactions. Maybe you have already checked this, but are you sure you
are committing all the transactions in your last sesssion ? that you
dont see on a reboot. Do you see any exceptions when running the
program that may cause a commit to not be issued ?
You could set derby.language.logStatementText=true and
derby.infolog.append=true and check the derby.log to look for commit
debug statements in there and what statements are executed.
Also, are you using any other derby properties for the database apart
from the derby.storage.fileSyncTransaction:Log=true ?
Thanks,
Sunitha.
This whole problem feels very much like a transaction log is not getting
committed and then is getting lost, or something of that nature. Should
we be doing anything special on system shutdown, to make sure everything
gets synced properly?
Thanks,
Scotty
