Using Data Affinity With Coherence 3.7.1 BroadKeyPartitioningStrategy Gives Missing/null Data (Doc ID 2304019.1)

Last updated on SEPTEMBER 04, 2017

Applies to:

Oracle Coherence - Version 3.7.1.9 and later
Information in this document applies to any platform.

Goal

Coherence deployment with 9 physical servers, with 4 storage nodes of 16GB each running on each server (36 storage nodes).


Data affinity (queries that use KeyAssociatedFilter, and key objects that use the KeyAssociation interface) is used to reduce CPU load on Coherence cache servers,. Number of associated keys (topics) is too small to spread evenly across all partitions (about 5000 possible key associations, with 8191 partitions), so BroadKeyPartitioningStrategy is used to spread each associated key across multiple partitions.

However, with this approach, for some data, invocations of NamedCache.getAll(key_collection) or NamedCache.get(key) return "null" instead of expected data. Some invocations of .get(key_collection) were returning "null" data for every key. 
 

Solution

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