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https://issues.apache.org/jira/browse/FLINK-18581?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17162073#comment-17162073
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Till Rohrmann commented on FLINK-18581:
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I found the first occurrence of {{Reference.tryHandlePending}} to be introduced
in OpenJDK with the version jdk8u72-b01
http://hg.openjdk.java.net/jdk8u/jdk8u/jdk/file/5ad1e9e8e841/src/share/classes/java/lang/ref/Reference.java.
This version should be already a couple of years old.
[~azagrebin] I think calling {{Reference.ReferenceHandler.run}} would not work
because it is an infinite loop.
I think this is price we are paying for using internal JVM methods which can
change across minor versions and which is very unfortunate. Let's keep this as
a warning for the future and let's try to avoid it.
I see two ways forward:
1) Only support Java8 version later or equal than jdk8u72-b01. This would
entail that we throw an appropriate exception with a clear message saying that
one needs to update the java version. The main problem I see with this approach
is whether other JVM implementation (other than OpenJDK) actually have the same
methods or not. Have we ever tried running Flink with a different JVM
implementation [~azagrebin]? Moreover, there is no guarantee that this method
won't disappear in some future version.
2) Getting rid of the clean up mechanism which relies on internal JVM methods
and implement our own mechanism. This solution which involve a much higher
effort, though.
Maybe there is also some middle ground by trying to call {{tryHandlerPending}}
and if this method does not exist to fall back to triggering the normal GC or
some other mean to trigger the clean up.
> Cannot find GC cleaner with java version previous 8u202
> -------------------------------------------------------
>
> Key: FLINK-18581
> URL: https://issues.apache.org/jira/browse/FLINK-18581
> Project: Flink
> Issue Type: Bug
> Components: Runtime / Coordination
> Affects Versions: 1.11.0
> Reporter: Xintong Song
> Priority: Critical
> Fix For: 1.12.0, 1.11.2
>
>
> {{JavaGcCleanerWrapper}} is looking for the package-private method
> {{Reference.tryHandlePending}} using reflection. However, the method is first
> introduced in the version 8u202. Therefore, if an older version JDK is used,
> the method cannot be found and Flink will fail.
> See also this [ML
> thread|http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Error-GC-Cleaner-Provider-Flink-1-11-0-td36565.html].
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