[SOLR-12739] Make autoscaling policy based replica placement the default strategy for placing replicas

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 7.6, 8.0
• Component/s: AutoScaling, SolrCloud
• Assignee: Shalin Shekhar Mangar
• Reporter: Shalin Shekhar Mangar
• Created: 05/Sep/18 15:59
• Updated: 18/Jul/20 15:48
• Resolved: 02/Nov/18 06:12

Description

Today the default placement strategy is the same one used since Solr 4.x which is to select nodes on a round robin fashion. I propose to make the autoscaling policy based replica placement as the default policy for placing replicas.

This is related to SOLR-12648 where even though we have default cluster preferences, we don't use them unless a policy is also configured.

Issue Links

• causes: SOLR-13248 Autoscaling based replica placement is broken out of the box
• causes: SOLR-14665 Collection creation is progressively slower
• is blocked by: SOLR-12836 ZkController creates a cloud solr client with no connection or read timeouts
• is blocked by: SOLR-12827 Migrate cluster wide defaults syntax in cluster properties to a nested structure
• relates to: SOLR-12845 Add a default cluster policy