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https://issues.apache.org/jira/browse/DERBY-4741?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12927345#action_12927345
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Knut Anders Hatlen commented on DERBY-4741:
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The sane jars are not intended for production use, so I wouldn't worry too much
about a performance loss that we only see with them. Unless it's getting so
slow that it takes an unreasonably long time to run the regression tests with
them, that is.
I'm guessing that the extra performance loss seen with sane jars is caused by
the assert in InterruptStatus.restoreIntrFlagIfSeen(LanguageConnectionContext),
which makes us look up the lcc in the context stack. Twice, actually. Perhaps
it would help a little to store the result from getContextOrNull() in a local
variable so that we get away with a single call. Or perhaps it's the
unconditional string concatenation for the message text that's costly. In any
case, that assert is the only place I can see that the patch would have a
different performance impact on sane and insane.
> Make Derby work reliably in the presence of thread interrupts
> -------------------------------------------------------------
>
> Key: DERBY-4741
> URL: https://issues.apache.org/jira/browse/DERBY-4741
> Project: Derby
> Issue Type: Bug
> Components: Store
> Affects Versions: 10.2.1.6, 10.2.2.0, 10.3.1.4, 10.3.2.1, 10.3.3.0,
> 10.4.1.3, 10.4.2.0, 10.5.1.1, 10.5.2.0, 10.5.3.0, 10.6.1.0
> Reporter: Dag H. Wanvik
> Assignee: Dag H. Wanvik
> Attachments: derby-4741-a-01-api-interruptstatus.diff,
> derby-4741-a-01-api-interruptstatus.stat,
> derby-4741-a-02-api-interruptstatus.diff,
> derby-4741-a-02-api-interruptstatus.stat,
> derby-4741-a-03-api-interruptstatus.diff,
> derby-4741-a-03-api-interruptstatus.stat,
> derby-4741-all+lenient+resurrect.diff, derby-4741-all+lenient+resurrect.stat,
> derby-4741-nio-container+log+waits+locks+throws.diff,
> derby-4741-nio-container+log+waits+locks+throws.stat,
> derby-4741-nio-container+log+waits+locks-2.diff,
> derby-4741-nio-container+log+waits+locks-2.stat,
> derby-4741-nio-container+log+waits+locks.diff,
> derby-4741-nio-container+log+waits+locks.stat,
> derby-4741-nio-container+log+waits.diff,
> derby-4741-nio-container+log+waits.stat, derby-4741-nio-container+log.diff,
> derby-4741-nio-container+log.stat, derby-4741-nio-container-2.diff,
> derby-4741-nio-container-2.log, derby-4741-nio-container-2.stat,
> derby-4741-nio-container-2b.diff, derby-4741-nio-container-2b.stat,
> derby.log, derby.log, MicroAPITest.java, xsbt0.log.gz
>
>
> When not executing on a small device VM, Derby has been using the Java NIO
> classes java.nio.clannel.* for file io.
> If thread is interrupted while executing blocking IO operations in NIO, the
> ClosedByInterruptException will get thrown. Unfortunately, Derby isn't
> current architected to retry and complete such operations (before passing on
> the interrupt), so the Derby database can be left in an inconsistent state
> and we therefore have to return a database level error. This means the
> applications can no longer access the database without a shutdown and reboot
> including a recovery.
> It would be nice if Derby could somehow detect and finish IO operations
> underway when thread interrupts happen before passing the exception on to the
> application. Derby embedded is sometimes embedded in applications that use
> Thread.interrupt to stop threads.
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