[
https://issues.apache.org/jira/browse/YARN-4024?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14703806#comment-14703806
]
Wangda Tan commented on YARN-4024:
----------------------------------
Thanks update, [~zhiguohong] and comments from [~sunilg].
bq. Since we use removeCache, I think update will be better suited as addToCache
+1, I think it's better to rename it to removeFromCache.
bq. Please add more comments and details about interface Resolver and its api.
I feel the api resolve has to be UnStable and Public for now. may be we can
separate the interface to another file.
Since it's an internal only interface, I think you should remove public for
them. And no need to add @Unstable and @public for such internal interfaces.
bq. LOG.debug("[" +...
Should be wrapped by isDebugEnabled
Regarding to tests, I think it maybe easier to expose a getResolver (just
default accessibility is fine) and mark it to be @VisibleForTesting like other
tests.
And it may be important to add a test to make sure DirectResolver will be
created to avoid future possible regression.
And I think it's better to modify check {{if (nodeIpCacheTimeout == -1) {}} to
be <= 0, since it doesn't make sense to have a timeout <= 0 for CachedResolver.
Thoughts?
> YARN RM should avoid unnecessary resolving IP when NMs doing heartbeat
> ----------------------------------------------------------------------
>
> Key: YARN-4024
> URL: https://issues.apache.org/jira/browse/YARN-4024
> Project: Hadoop YARN
> Issue Type: Improvement
> Reporter: Wangda Tan
> Assignee: Hong Zhiguo
> Attachments: YARN-4024-draft-v2.patch, YARN-4024-draft-v3.patch,
> YARN-4024-draft.patch, YARN-4024-v4.patch
>
>
> Currently, YARN RM NodesListManager will resolve IP address every time when
> node doing heartbeat. When DNS server becomes slow, NM heartbeat will be
> blocked and cannot make progress.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
