[ 
https://issues.apache.org/jira/browse/QPID-6387?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Keith Wall updated QPID-6387:
-----------------------------
    Affects Version/s: 0.18
                       0.22
                       0.30

> ChannelToSessionMap/IdToConsumerMap array optimisation publishes in thread 
> unsafe manner
> ----------------------------------------------------------------------------------------
>
>                 Key: QPID-6387
>                 URL: https://issues.apache.org/jira/browse/QPID-6387
>             Project: Qpid
>          Issue Type: Bug
>          Components: Java Client
>    Affects Versions: 0.18, 0.22, 0.30
>            Reporter: Keith Wall
>            Assignee: Keith Wall
>             Fix For: 0.31
>
>
> Two internal classes within the Java Client (ChannelToSessionMap / 
> IdToConsumerMap) use an optimisation which hopes to permit 'fast access' 
> first sixteen sessions (or consumers) by making use on an array.    The array 
> is written by one thread and then read by others.  Unfortunately,  the 
> read/writes are not protected using a memory barrier so it is possible a 
> thread may see a stale value, and this could lead to incorrect program 
> behaviour.
> It is safer (and simpler) to replace the data structure with one backed by a 
> ConcurrentHashMap.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to