Hadoop / Hive upgrade performance -


we testing hive , hadoop digging in our data , installed while hadoop 1.2.1 , hive 0.11 (was stable version)

test server 4 cores , 16gb of ram.

now wanted know if switching hive 0.12 , hadoop 2.2 worth trouble of upgrading server in terms of performance on queries?

a query looks this:

select i, day(time), count(distint value), count(*) table lateral view explode(column) tab group i, day(time);

so bit of in query used couldn't find decent info on performance gain when upgrading.

any insight on matter nice :)

cheers

since query doesn't contain "where" predicate, cannot enjoy predicate pushdown storage layer introduced in 0.12, if data in orc format.

thus, although among 0.12 improvements faster plan generation , optimization count, educated guess, believe, should performance improvement not dramatic.


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