[SOLR-6730] select?replicaAffinity=(node|host) and replicaAffinity.hostPriorities support

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Later
• Assignee: Unassigned
• Reporter: Christine Poerschke
• Created: 11/Nov/14 17:03
• Updated: 15/Feb/19 19:40
• Resolved: 15/Feb/19 19:37

Description

If no shards parameter is supplied with a select request then sub-requests will go to a random selection of live solr nodes hosting shards for the collection of interest. All sub-requests must complete before results can be collated i.e. the slowest sub-request determines how fast the search completes.

Use of optional replicaAffinity can reduce the number of JVMs hit by a given search (the more JVMs are hit, the higher the chance of hitting a garbage collection pause in one of many JVMs). Preferentially directing requests to certain areas of the cloud can also be useful for debugging or when some replicas reside on 'faster' machines.

Issue Links

• depends upon: SOLR-8332 factor HttpShardHandler[Factory]'s url shuffling out into a ReplicaListTransformer class
• depends upon: SOLR-8298 small preferLocalShards implementation refactor
• relates to: SOLR-13258 'sticky' replica affinity support
• relates to: SOLR-13257 Enable replica routing affinity for better cache usage