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https://issues.apache.org/jira/browse/HIVE-22492?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17278872#comment-17278872
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Ádám Szita commented on HIVE-22492:
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Hey [~bslim] - can you please elaborate on what was the justification to set
the lambda to 0.1 as part of this change?
(
[https://github.com/apache/hive/commit/0781cf2c5104dafd0c5496631cafabac9d59df67#diff-b7bbe8545a21ec7d7e9cfe40ef66444789e332996aaa9e7f1430dbe4822a2c9cR4123]
)
> Amortize lock contention due to LRFU accounting
> -----------------------------------------------
>
> Key: HIVE-22492
> URL: https://issues.apache.org/jira/browse/HIVE-22492
> Project: Hive
> Issue Type: Improvement
> Reporter: Slim Bouguerra
> Assignee: Slim Bouguerra
> Priority: Major
> Fix For: 4.0.0
>
> Attachments: HIVE-22492.2.patch, HIVE-22492.patch,
> llap-lock-contention.svg
>
>
> LRFU eviction policy can be a major source of contention under high load.
> This can be see on the following profiles.
> To fix this the idea is to use a batching wrapper to amortize the locking
> contention.
> The trick i a common way to amortize locking as explained here
> http://www.ece.eng.wayne.edu/~sjiang/pubs/papers/ding-09-BP-Wrapper.pdf
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