[ 
https://issues.apache.org/jira/browse/JENA-1785?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16985399#comment-16985399
 ] 

Andy Seaborne commented on JENA-1785:
-------------------------------------

The updated one fails nearly every time for me - bumping up the 1000 to 2000 
makes it certain. Hashing is involved so it isn't so surprising.

> A newly created node can remain invisible after commit
> ------------------------------------------------------
>
>                 Key: JENA-1785
>                 URL: https://issues.apache.org/jira/browse/JENA-1785
>             Project: Apache Jena
>          Issue Type: Bug
>          Components: TDB2
>    Affects Versions: Jena 3.13.0, Jena 3.13.1
>            Reporter: Pavel Mikhailovskii
>            Assignee: Andy Seaborne
>            Priority: Critical
>         Attachments: TestVisibilityOfChanges.java
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> A node once marked as non-present (_NodeTableCache.nonPresent_) can remain 
> invisible even after it's created and the transaction is committed. That 
> might happen because there's no guarantee that *all* newly created nodes will 
> be eventually added to the "base" version _ThreadBufferingCache.baseCache_ of 
> theĀ _node2id_Cache_ (as the _localCache_ has limited capacity) or removed 
> from the "base" version of the _nonPresent_ cache (even if they were, there 
> would still be a chance of re-adding them by some read transaction). 
> The simplest fix is to get rid of the _nonPresent_ cache which seems to be of 
> limited use anyway. A more sophisticated fix would involve keeping track of 
> all newly allocated nodes and their removal from the base version of 
> _nonPresent_ cache on transaction commit.
> To reproduce: see the attached test.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to