Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: <derby-dev@db.apache.org>
Message-ID: <1265064427.1240922730327.JavaMail.jira@brutus>
Date: Tue, 28 Apr 2009 05:45:30 -0700 (PDT)
From: "Knut Anders Hatlen (JIRA)" <jira@apache.org>
To: derby-dev@db.apache.org
Subject: [jira] Updated: (DERBY-4193) ASSERT FAILED Scan position already
 saved with multi-threaded insert/update/delete
In-Reply-To: <150744071.1240876770522.JavaMail.jira@brutus>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


     [ https://issues.apache.org/jira/browse/DERBY-4193?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Knut Anders Hatlen updated DERBY-4193:
--------------------------------------

    Attachment: d4193-1a.diff

The attached patch adds a test case to IndexSplitDeadlockTest that fails most of the time (there is a race for a lock, so that it sometimes doesn't fail) with the assert failure reported by Kathey.

The patch also changes BTreeMaxScan.positionAtStartPosition() so that it uses lockNonScanPreviousRow() instead of lockScanRow(). This change makes both IndexSplitDeadlockTest and ScanPosSaved run without errors.

> ASSERT FAILED Scan position already saved with multi-threaded insert/update/delete 
> -----------------------------------------------------------------------------------
>
>                 Key: DERBY-4193
>                 URL: https://issues.apache.org/jira/browse/DERBY-4193
>             Project: Derby
>          Issue Type: Bug
>          Components: Store
>    Affects Versions: 10.5.1.1, 10.6.0.0
>         Environment: Windows XP, IBM 1.6 SR6, Sun  1.6.0_01-b06
>            Reporter: Kathey Marsden
>            Assignee: Knut Anders Hatlen
>         Attachments: d4193-1a.diff, ScanPosSaved.java, ScanPosSaved.java
>
>
> The attached program ScanPosSaved.java produces the error below, fairly quickly.  
> The program has three threads, one doing inserts into a table with an identity column, one updating the row with the maximum id, one deleting the row with the maximum id.
> To reproduce, run >java ScanPosSaved  and <ctrl> <c> out of the program after you get the error.
> I saw this 10.5 and trunk sane builds but did not see it on 10.4.  With the insane build of 10.5.1.1 (RC2) I did not see any symptoms right away, so don't know how serious an issue this is for insane builds.
> org.apache.derby.shared.common.sanity.AssertFailure: ASSERT FAILED Scan position already saved
> 	at org.apache.derby.shared.common.sanity.SanityManager.ASSERT(SanityManager.java:120)
> 	at org.apache.derby.impl.store.access.btree.BTreeScan.savePositionAndReleasePage(BTreeScan.java:2148)
> 	at org.apache.derby.impl.store.access.btree.BTreeScan.savePositionAndReleasePage(BTreeScan.java:2212)
> 	at org.apache.derby.impl.store.access.btree.BTreeRowPosition.saveMeAndReleasePage(BTreeRowPosition.java:128)
> 	at org.apache.derby.impl.store.access.btree.index.B2IRowLocking3.lockRowOnPage(B2IRowLocking3.java:295)
> 	at org.apache.derby.impl.store.access.btree.index.B2IRowLocking3._lockScanRow(B2IRowLocking3.java:599)
> 	at org.apache.derby.impl.store.access.btree.index.B2IRowLockingRR.lockScanRow(B2IRowLockingRR.java:105)
> 	at org.apache.derby.impl.store.access.btree.BTreeMaxScan.positionAtStartPosition(BTreeMaxScan.java:347)
> 	at org.apache.derby.impl.store.access.btree.BTreeMaxScan.fetchMax(BTreeMaxScan.java:434)
> 	at org.apache.derby.impl.store.access.btree.index.B2I.fetchMaxOnBTree(B2I.java:739)
> 	at org.apache.derby.impl.store.access.RAMTransaction.fetchMaxOnBtree(RAMTransaction.java:1078)
> 	at org.apache.derby.impl.sql.execute.LastIndexKeyResultSet.openCore(LastIndexKeyResultSet.java:189)
> 	at org.apache.derby.impl.sql.execute.ProjectRestrictResultSet.openCore(ProjectRestrictResultSet.java:168)
> 	at org.apache.derby.impl.sql.execute.ScalarAggregateResultSet.openCore(ScalarAggregateResultSet.java:133)
> 	at org.apache.derby.impl.sql.execute.ProjectRestrictResultSet.openCore(ProjectRestrictResultSet.java:168)
> 	at org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl.open(BasicNoPutResultSetImpl.java:245)
> 	at org.apache.derby.impl.sql.GenericPreparedStatement.executeStmt(GenericPreparedStatement.java:416)
> 	at org.apache.derby.impl.sql.GenericPreparedStatement.execute(GenericPreparedStatement.java:297)
> 	at org.apache.derby.impl.jdbc.EmbedStatement.executeStatement(EmbedStatement.java:1235)
> 	at org.apache.derby.impl.jdbc.EmbedStatement.execute(EmbedStatement.java:625)
> 	at org.apache.derby.impl.jdbc.EmbedStatement.executeQuery(EmbedStatement.java:152)
> 	at ScanPosSaved.updateOperation(ScanPosSaved.java:62)
> 	at ScanPosSaved$3.run(ScanPosSaved.java:17)
> I discovered this when trying to get a smaller repro for DERBY-4181, but I think it is a different issue, because it reproduces on multiple jvms and does not reproduce on 10.4.  The assertion was added with DERBY-2991.  Knut could you perhaps assess how serious this is?

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