[SLING-9482] Seed the cache from offset persisted in the source repository

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Content Distribution Journal Core 0.1.16
• Component/s: Content Distribution
• Assignee: Timothee Maret
• Reporter: Timothee Maret
• Created: 28/May/20 15:30
• Updated: 23/Jun/20 08:28
• Resolved: 03/Jun/20 21:10

Description

The approach taken in SLING-9460 to avoid sending seeding messages does not address some scenarios like publishing content without subscriber agents. Without subscriber agents.

To be sure we always have a recent seed available, we should persist seed offsets in the source repository (typ. author) and seed caches from it. We do have the local store class that allows to easily write the offsets in the repository. To not stress the repository too much, we should batch those writes (e.g. 1 offset update every 10 package processed). To support a cluster, the writes must be initiated only from the cluster leader instance.

Issue Links

• relates to: SLING-9474 Bad partition when using an empty package topic
• supercedes: SLING-9460 Avoid seeding messages in PubQueueCache
• links to: GitHub Pull Request #40