[JBoss JIRA] (ISPN-2103) Concurrent access after removal of an AtomicMap should NOT result in an IllegalStateException when accessed by other threads
by Radoslav Husar (JIRA)
[ https://issues.jboss.org/browse/ISPN-2103?page=com.atlassian.jira.plugin.... ]
Radoslav Husar commented on ISPN-2103:
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[~pruivo] If I understand the question the right approach seems to be throwing an ISE here, we can't just recreate removed structures.
> Concurrent access after removal of an AtomicMap should NOT result in an IllegalStateException when accessed by other threads
> ----------------------------------------------------------------------------------------------------------------------------
>
> Key: ISPN-2103
> URL: https://issues.jboss.org/browse/ISPN-2103
> Project: Infinispan
> Issue Type: Bug
> Components: Core
> Affects Versions: 5.1.5.FINAL
> Reporter: Adrian Nistor
> Assignee: Pedro Ruivo
>
> ISPN-1121 introduces an IllegalStateException that is being thrown from AtomicMap methods once the map handle has become stale (ie. removed from cache). In case of concurrent access, the exception is thrown to all threads not just to the thread that performed the removal. This was fine-ish in older versions of Infinispan before introduction of optimistic and pessimistic locking but it should be reconsidered now because:
> 1. It interferes/overlaps with transaction isolation. We should rely on the selected locking scheme (OL/PL) to detect conflicts between transactions and report the problem accordingly. Especially if the stale map is used just for reading - this should be allowed to work rather than stop it.
> 2. This exception is pretty disruptive and awkward to handle. All methods of an AtomicMap can result in this exception and the current thread has to be prepared for handling it if other threads remove the map. Not much transaction isolation.
> 3. Since the TreeCache is backed by AtomicMap nearly all Tree API can throw this.
> The proposed fix consists of:
> 1. removing AtomicHashMap.removed flag and AtomicHashMap.markRemoved() method.
> 2. revising AtomicHashMapProxy.assertValid() method to check only if the map is null (ie. removed) but no longer use the removed flag.
> 3. revising ReadCommittedEntry.commit() method to no longer call markRemoved() method.
> The consequences of these changes are:
> 1. Any further access to a stale map results in IllegalStateException ONLY in the thread that performed the removal. This thread 'knows' the map is stale so it is fine to punish it. Other threads remain unaffected until lock acquisition or commit is performed (depending on locking model).
> 2. Other threads can continue to use the previously obtained map handle for reads without danger of getting an exception.
> 3. If a write operation is done on the map, the results depend on the locking model:
> 3.1 optimistic locking + write skew check: a WriteSkewException will stop the commit during prepare
> 3.2 optimistic locking, no write skew check: the write is committed and the work of the transaction that removed the map is overwritten. The map is effectively revived.
> 3.3 pessimistic locking: same as 3.2
> Please note 3.2 and 3.3 work the same as for normal values (not atomic maps).
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[JBoss JIRA] (ISPN-7351) Support @Named in CDI extension
by Sebastian Łaskawiec (JIRA)
[ https://issues.jboss.org/browse/ISPN-7351?page=com.atlassian.jira.plugin.... ]
Sebastian Łaskawiec commented on ISPN-7351:
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Indeed, both those things are separate. Currently {{@Named}} annotation is simply ignored. Adding support for it shouldn't be that hard.
I also think that using multiple {{@ConfigureCache}} annotations might be a good idea. This way we will have more flexibility.
I'll try to address both those things in a single go (since they are somewhat related to each other).
> Support @Named in CDI extension
> -------------------------------
>
> Key: ISPN-7351
> URL: https://issues.jboss.org/browse/ISPN-7351
> Project: Infinispan
> Issue Type: Feature Request
> Components: CDI Integration
> Reporter: Sebastian Łaskawiec
> Assignee: Sebastian Łaskawiec
>
> Currently our users have to create lots and lots of {{@Qualifier}} type of annotations. It would be desirable to support {{@Named("driver")}} type of annotations.
> Useful links:
> * {{@Named}} Javadoc: http://docs.oracle.com/javaee/6/api/javax/inject/Named.html
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