db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Paul Sabatino (JIRA)" <j...@apache.org>
Subject [jira] Commented: (DERBY-151) Thread termination -> XSDG after operation is 'complete'
Date Mon, 11 Feb 2008 14:52:08 GMT

    [ https://issues.apache.org/jira/browse/DERBY-151?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12567653#action_12567653

Paul Sabatino commented on DERBY-151:

We ran into this same error when running our application over slow network connections. At
first we didn't see the connection between the network and the derby error until we started
to investigate interrupts. We found that if a thread was ever interrupted and you attempt
a commit on that same thread you'll see this error. It seems to be linked to having the threads
interrupted flag set.

Here's how to test it:
1. add a  Thread.interrupted(); right after the interrupt() in the attached test program d151.java.
(this clears the interrupted flag)
2. Make sure the DB directory is deleted and rerun the test. It will now complete.

I managed to fix our application by adjusting our network layer to clear the interrupted flag
when we timed out an IO operation. That was how our issue was related to a slow network and
not a local disk problem.

The error message is misleading since it seems to indicate that there's a problem writing
to the file, when really it just misinterpreted the interrupted flag to mean the channel was
closed. You might want to fix how the interrupts are checked.

> Thread termination -> XSDG after operation is 'complete'
> --------------------------------------------------------
>                 Key: DERBY-151
>                 URL: https://issues.apache.org/jira/browse/DERBY-151
>             Project: Derby
>          Issue Type: Bug
>          Components: Store
>    Affects Versions:
>         Environment: Linux kernel 2.4.21-243-athlon (SuSE 9.0)
>            Reporter: Barnet Wagman
>         Attachments: d151.java, derby.log
> I've encountered what appears to be a bug related to threading. After an INSERT operation,
if the invoking thread terminates too quickly, Derby throws an XSDG.
> The bug is a bit difficult to isolate but it occurs consistently in the following situation
(with a particular database and an operation of a particular size):
> Derby is running in embedded mode with autocommit on.  
> The application performs an INPUT operation from a thread that is not the main thread.
 The INPUT is issued using a PreparedStatement.  The INPUT adds ~ 256 records of six fields
each. (Note that INSERTs of this size seem to work fine in other contexts.)
> The preparedStatement.executeUpdate() seems to excute successfully; at least it returns
without throwing an exception. 
> The thread that invoked the INPUT operation then terminates (but NOT the application).
 The next INPUT operation then results in an
> "ERROR XSDG1: Page Page(7,Container(0, 1344)) could not be written to disk, please check
if disk is full."
> The disk is definitely not full.
> HOWEVER, if I put the calling thread to sleep for a second before it exits, the problem
does not occur.
> I'm not quite sure what to make of this.  I was under the impression that most of Derby's
activity occurs in the application's threads.  Could Derby be creating a child thread from
in the application thread, which dies when the parent thread terminates?
> Thanks

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

View raw message