[AMQ-3188] Full table scan for durable subs in jdbc store when priority enabled; very slow with large message backlog

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 5.4.2
• Fix Version/s: 5.5.0
• Component/s: Message Store
• Labels: DurableSubscriptions JDBC, Performance Topic

Environment

JDBC

• Assignee: Gary Tully
• Reporter: Gary Tully
• Created: 22/Feb/11 18:42
• Updated: 02/Mar/11 16:17
• Resolved: 22/Feb/11 18:54

Description

Priority support is delegate to the DB, but it currently requires a full table scan to recover a new batch of messages. This can be very slow when the message table is large (a consumer has been offline for some time). With multiple concurrent consumers this gets worse.
The store needs to use more internal state w.r.t priority such that simpler/faster queries are used.

Issue Links

• is related to: AMQ-3196 Speed up initial message delivery for offline durable sub with keepDurableSubsActive=true and JDBC store