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https://issues.apache.org/jira/browse/IMPALA-2277?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Tim Armstrong resolved IMPALA-2277.
-----------------------------------
Resolution: Later
We switched to FastHash in some places.
* CRC is very cheap to evaluate and it's hard to outdo for short data types in
perf-critical places like hash join
* FastHash is good for mixed data where we want a higher quality hash function,
e.g. data distribution in an exchange
* Many other hash functions only have benefits on long strings.
> Investigate alternative hash functions
> --------------------------------------
>
> Key: IMPALA-2277
> URL: https://issues.apache.org/jira/browse/IMPALA-2277
> Project: IMPALA
> Issue Type: Task
> Components: Backend
> Affects Versions: Impala 2.2
> Reporter: Tim Armstrong
> Priority: Minor
>
> Impala currently uses FNV, Murmur2 and CRC hashes in different places
> depending on requirements. There are additional, newer, hash functions
> available including Murmur3, SpookyHash, CityHash, and others that may offer
> benefits.
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