flink-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF GitHub Bot (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (FLINK-1789) Allow adding of URLs to the usercode class loader
Date Wed, 30 Sep 2015 15:12:04 GMT

    [ https://issues.apache.org/jira/browse/FLINK-1789?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14936972#comment-14936972

ASF GitHub Bot commented on FLINK-1789:

Github user twalthr commented on the pull request:

    @mxm I updated the JIRA description with the most important comments of the discussion.

> Allow adding of URLs to the usercode class loader
> -------------------------------------------------
>                 Key: FLINK-1789
>                 URL: https://issues.apache.org/jira/browse/FLINK-1789
>             Project: Flink
>          Issue Type: Improvement
>          Components: Distributed Runtime
>            Reporter: Timo Walther
>            Assignee: Timo Walther
>            Priority: Minor
> Currently, there is no option to add customs classpath URLs to the FlinkUserCodeClassLoader.
JARs always need to be shipped to the cluster even if they are already present on all nodes.
> It would be great if RemoteEnvironment also accepts valid classpaths URLs and forwards
them to BlobLibraryCacheManager.
> The problem with the current approach is that the code loaded by the regular JVM class
loader cannot refer to job specific types (which can be accessed only at the UserCodeClassLoader
level). Unfortunately, this is the case if we use the classpath entry to generate the dataflows
dynamically at runtime.
> Currently this functionality needs to be done by "hacks" (hardcode a filesystem path
next to the list of jars when initializing the BlobManager entry). It makes sense to open
an issue which makes this list parameterizable via an additional ExecutionEnvironment argument
(this is basically the only main feature which prohibits the use of Emma project with "off-the-shelf"
> This, of course, would require that the folders are shared (e.g. via NFS) between client,
master and workers. I think what made Stephan so excited is the idea of using the same URL
mechanism in order to ship the code to all dependent parties (most probably by running a dedicated
HTTP or FTP server on the client).
> We make the following assumptions for the use case where we need the global class path:
> - The URL is either a file path that points to a directory accessible to all nodes (NFS
or so) and the client runs in the cluster as well.
> - The URL is an HTTP URL or so that points to a file server that serves the classes to
work in non-shared directory settings.

This message was sent by Atlassian JIRA

View raw message