[SLING-6503] Concurrency issue can prevent repository packages to be cleaned up

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Content Distribution Core 0.1.18
• Fix Version/s: Content Distribution Core 0.2.0
• Component/s: Content Distribution
• Flags: Patch
• Assignee: Timothee Maret
• Reporter: Timothee Maret
• Created: 01/Feb/17 16:00
• Updated: 02/Mar/17 10:00
• Resolved: 03/Feb/17 15:06

Description

In SCD setups with more than one export queue and storing packages in the repository, packages may not be collected after being distributed to all queues.

This is typically the case on the author instance of a Sync setup.

The current implementation [0] stores a resource in the repository in order to keep track of each consumer of the package. When each consumer is done distributing to its queue, it checks if there is no more registered resources and remove the package if it is the case.

The problem is that consumers run concurrently and without synchronisation, thus leading to situation where all consumers concurrently observe remaining consumers and the cleanup is never executed.

[0] https://github.com/apache/sling/blob/trunk/contrib/extensions/distribution/core/src/main/java/org/apache/sling/distribution/packaging/impl/ResourceDistributionPackage.java

Issue Links

• is related to: SLING-6589 DistributionPackageUtils#disposable should handle hanging packages