[SLING-10854] Introduce cleanup job of old slingId data in discovery

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Discovery Oak 1.2.34
• Fix Version/s: Discovery Oak 1.2.44
• Component/s: Discovery
• Assignee: Stefan Egli
• Reporter: Stefan Egli
• Created: 06/Oct/21 07:41
• Updated: 03/Apr/23 12:32
• Resolved: 14/Mar/23 09:23

Description

Discovery.oak stores nodes and properties per slingId under /var/discovery/oak. In a scenario where the slingIds are stable things are fine. If the slingIds change frequently, old slingId-related data stays as garbage and accumulates.

We should introduce a cleanup job to delete old slingId data. The leader could execute this to avoid race conditions. We might need to add some additional property to indicate age of slingIds (there's already the /var/discovery/oak/clusterInstances/leaderElectionIdCreatedAt property which gets updated upon each discovery.oak bundle activation - but it's somewhat indirect. Having a new, dedicated property sounds cleaner (this one could be used to clean up old data though)