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https://issues.apache.org/jira/browse/SPARK-13328?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15150863#comment-15150863
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Apache Spark commented on SPARK-13328:
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User 'nezihyigitbasi' has created a pull request for this issue:
https://github.com/apache/spark/pull/11241
> Possible poor read performance for broadcast variables with dynamic resource
> allocation
> ---------------------------------------------------------------------------------------
>
> Key: SPARK-13328
> URL: https://issues.apache.org/jira/browse/SPARK-13328
> Project: Spark
> Issue Type: Bug
> Components: Spark Core
> Affects Versions: 1.5.2
> Reporter: Nezih Yigitbasi
>
> When dynamic resource allocation is enabled fetching broadcast variables from
> removed executors were causing job failures and SPARK-9591 fixed this problem
> by trying all locations of a block before giving up. However, the locations
> of a block is retrieved only once from the driver in this process and the
> locations in this list can be stale due to dynamic resource allocation. This
> situation gets worse when running on a large cluster as the size of this
> location list can be in the order of several hundreds out of which there may
> be tens of stale entries. What we have observed is with the default settings
> of 3 max retries and 5s between retries (that's 15s per location) the time it
> takes to read a broadcast variable can be as high as ~17m (below log shows
> the failed 70th block fetch attempt where each attempt takes 15s)
> {code}
> ...
> 16/02/13 01:02:27 WARN storage.BlockManager: Failed to fetch remote block
> broadcast_18_piece0 from BlockManagerId(8, ip-10-178-77-38.ec2.internal,
> 60675) (failed attempt 70)
> ...
> 16/02/13 01:02:27 INFO broadcast.TorrentBroadcast: Reading broadcast variable
> 18 took 1051049 ms
> {code}
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