[
https://issues.apache.org/jira/browse/GEODE-8671?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17294672#comment-17294672
]
ASF subversion and git services commented on GEODE-8671:
--------------------------------------------------------
Commit dabb610b74bb0b27603d7803ec3cdd1cbb16c43f in geode's branch
refs/heads/develop from Jianxia Chen
[ https://gitbox.apache.org/repos/asf?p=geode.git;h=dabb610 ]
GEODE-8671: Two threads calling get and retrieve the same PdxInstance,
resulting in corruption (#5925)
For PdxInstance, return a new reference in LocalRegion.optimizedGetObject(),
instead of using the value in the Future. This is to avoid Pdx corruption when
multiple threads share the same reference of PdxInstance.
> Two threads calling get and retrieve the same PdxInstance, resulting in
> corruption
> ----------------------------------------------------------------------------------
>
> Key: GEODE-8671
> URL: https://issues.apache.org/jira/browse/GEODE-8671
> Project: Geode
> Issue Type: Improvement
> Components: regions
> Reporter: Dan Smith
> Assignee: Jianxia Chen
> Priority: Major
> Labels: blocks-1.14.0, pull-request-available
>
> Even if copy-on-read is set to true, two threads calling get on a partitioned
> region can end up with the same PdxInstance object.
> This is problematic because some PdxInstances methods are not thread safe.
> Although the underlying bytes are immutatable, the PDXInstance has a
> ByteSource with a position field that changes. That means two threads doing
> serialization or calling toString on the PdxInstance could result in one or
> more threads getting a corrupt read.
> It looks like they are ending up with the same instance because of the
> behavior in LocalRegion.optimizedGetObject. We use futures to make sure there
> is only 1 get that goes through, and both threads receive the same value.
>
> Ending up in optimizedGetObject requires a race with the put, because if the
> value was in the cache at the beginning of the get it would be returned
> earlier in the get process.
> I put a test that reproduces this issue here -
> https://github.com/upthewaterspout/geode/pull/new/feature/pdx-instances-shared
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
