db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dag H. Wanvik (JIRA)" <j...@apache.org>
Subject [jira] Commented: (DERBY-4741) Make Derby work reliably in the presence of thread interrupts
Date Tue, 02 Nov 2010 14:52:28 GMT

    [ https://issues.apache.org/jira/browse/DERBY-4741?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12927445#action_12927445
] 

Dag H. Wanvik commented on DERBY-4741:
--------------------------------------

Knut is right, that was the expensive assert I mentioned before (in sane builds). Since this
is a micro benchmark that mainly measures the CPU neeeded to execute ResultSet.next when data
is cached in memory, the effect of the assert shows up heavily. Running a profiling I saw
the string concatenation there being dominant. No, I did not notice the regression test become
slower, but if the turns out to be an issue, it is easy enough to comment out the asset. For
now, I'll change the assert code to just call  getContextOrNull once.


> 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.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message