[
https://issues.apache.org/jira/browse/GEODE-4083?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16289709#comment-16289709
]
ASF GitHub Bot commented on GEODE-4083:
---------------------------------------
dschneider-pivotal commented on a change in pull request #1161: GEODE-4083: fix
infinite loop caused by thread race changing version
URL: https://github.com/apache/geode/pull/1161#discussion_r156746797
##########
File path:
geode-core/src/main/java/org/apache/geode/internal/cache/versions/RegionVersionVector.java
##########
@@ -574,17 +609,20 @@ public void initializeVersionHolder(T mbr,
RegionVersionHolder<T> otherHolder) {
}
}
- private void updateLocalVersion(long version) {
- boolean repeat = false;
+ void updateLocalVersion(long newVersion) {
+ boolean needToUpdate;
Review comment:
I don't like the name "needToUpdate". I think a better name would be
"needToTrySetAgain". It is only set to true when the compareAndSet fails and we
need to retry. If it is set to true it does not mean we "needToUpdate" we just
need to check again.
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
> RegionVersionVector.updateLocalVersion can go into an infinite loop
> -------------------------------------------------------------------
>
> Key: GEODE-4083
> URL: https://issues.apache.org/jira/browse/GEODE-4083
> Project: Geode
> Issue Type: Bug
> Components: regions
> Reporter: Darrel Schneider
> Assignee: Eric Shu
>
> RegionVersionVector.updateLocalVersion can go into an infinite loop.
> The problem is this code:
> {code}
> private void updateLocalVersion(long version) {
> boolean repeat = false;
> do {
> long myVersion = this.localVersion.get();
> if (myVersion < version) {
> repeat = !this.localVersion.compareAndSet(myVersion, version);
> }
> } while (repeat);
> }
> {code}
> if version is "1" and localVersion.get() returns "0" the first time it is
> called but then compareAndSet returns false because localVersion has changed
> to "2" then the loop will never terminate because repeat will always be false
> and myVersion ("2" or more) will never be less than version ("1").
> The simple fix is to be sure repeat is set to false when myVersion is >= to
> version.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
