You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@tapestry.apache.org by "Marcus Schulte (JIRA)" <de...@tapestry.apache.org> on 2008/08/25 20:15:44 UTC

[jira] Resolved: (TAPESTRY-2382) Possible deadlock in ExpressionCacheImpl (on _lock instance)

     [ https://issues.apache.org/jira/browse/TAPESTRY-2382?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Marcus Schulte resolved TAPESTRY-2382.
--------------------------------------

    Resolution: Fixed

> Possible deadlock in ExpressionCacheImpl (on _lock instance)
> ------------------------------------------------------------
>
>                 Key: TAPESTRY-2382
>                 URL: https://issues.apache.org/jira/browse/TAPESTRY-2382
>             Project: Tapestry
>          Issue Type: Bug
>          Components: Framework
>    Affects Versions: 4.1.3
>            Reporter: Alexander Gavrilov
>            Assignee: Marcus Schulte
>            Priority: Critical
>             Fix For: 4.1.6
>
>
> Under some circumstances deadlock occurs in the ExpressionCacheImpl. 
> 1)Thread  Ta opening a Page Pa. Page Pa does not bound  to the current request  cycle, so new Instance requested from PageSource and current thread enter to the  synchronized _pool.borrowObject(key) 
> 2) At this time thread Tb render page Pb, and for some property evaluates expression binding. So ExpressionCacheImpl's _lock locked by thread Tb. Result of expression evaluation is a reference to the Page Pc instance, which is not bound to the current thread, so new Instance requested from PageSource and current thread tried to enter to the  synchronized _pool.borrowObject(key) which is locked by Ta. 
> 3) Thread Ta worked creating new Page Pa Instance, which is not exists in the pool, so a new Page instance should be created. In the proccess of parsing page loader try to evaluate expression binding and try to lock a ExpressionCacheImpl's _lock, which is locked by thread Tb. 
> 4) Whe have a deadlock, so no new page instance and expression could be created and evaluated. 
> This causes a serios problems while  system  startup, so we need to restart our app many times, untill it warmed up.

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


---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@tapestry.apache.org
For additional commands, e-mail: dev-help@tapestry.apache.org