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https://issues.apache.org/jira/browse/HIVE-396?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12740431#action_12740431
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Yuntao Jia commented on HIVE-396:
---------------------------------
Can you check how many jobs are there in the Hive query? If there are two, it
means the output from Hive are merged to a single file by running an additional
map-reduce job. If that is the case, you can turn it off by change the
following property in Hive-default.xml to FALSE (it is true by default).
hive.merge.mapfiles true
"Merge small files at the end of a map-only job"
Other than that, I have no idea why Hive is so slow.
> Hive performance benchmarks
> ---------------------------
>
> Key: HIVE-396
> URL: https://issues.apache.org/jira/browse/HIVE-396
> Project: Hadoop Hive
> Issue Type: New Feature
> Reporter: Zheng Shao
> Assignee: Yuntao Jia
> Attachments: hive_benchmark_2009-06-18.pdf,
> hive_benchmark_2009-06-18.tar.gz, hive_benchmark_2009-07-12.pdf,
> hive_benchmark_2009-07-21.tar.gz
>
>
> We need some performance benchmark to measure and track the performance
> improvements of Hive.
> Some references:
> PIG performance benchmarks PIG-200
> PigMix: http://wiki.apache.org/pig/PigMix
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