[IGNITE-14769] Key hash calculation.

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha4
• Labels: iep-54 ignite-3
• Ignite Flags: Docs Required, Release Notes Required
• Assignee: Konstantin Orlov
• Reporter: Andrey Mashenkov
• Created: 24/May/21 08:01
• Updated: 10/Jul/23 06:44
• Resolved: 08/Dec/21 15:22

Description

There are next possible ways for cache calculation.

1. Update hash on every write method call as it works for now.
2. Calculate for all key chunk (hash of byte[]) - all columns including a null-map.

Let's choose and implement the best way and along with a better hash function,
e.g. xxHash64 [1], Murmur3 [2]released in Apache Commons, CityHash (from Google) [3], FastHash32 [4].

 

[1]https://github.com/Cyan4973/xxHash/

[2]https://commons.apache.org/proper/commons-codec/jacoco/org.apache.commons.codec.digest/MurmurHash3.java.html

[3] https://github.com/google/cityhash

[4] https://github.com/rurban/smhasher/blob/master/fasthash.cpp

Issue Links

• causes: IGNITE-19935 Allow combining individual colocation hashes
• links to: GitHub Pull Request #478
• links to: PR