Gary Tully created AMQ-6164:
-------------------------------
Summary: queue sendLock prevents concurrent journal updates
Key: AMQ-6164
URL: https://issues.apache.org/jira/browse/AMQ-6164
Project: ActiveMQ
Issue Type: Improvement
Components: Broker, Message Store
Affects Versions: 5.13.0
Reporter: Gary Tully
Assignee: Gary Tully
Fix For: 5.14.0
concurrent producers contend on the queue sendlock rather than on the journal,
preventing batching or in the case of jdbc, concurrent writes to the db.
The sendlock protects message order, however order is ultimately determined by
the sequence id assigned by the persistence adapter.
The ground work for aligning the cursors with the journal sequence ids was
layed in https://issues.apache.org/jira/browse/AMQ-4485 and
https://issues.apache.org/jira/browse/AMQ-5266
With the ordering between transacted and non transacted producers overlapping
the cursor already respects the journal ordering, the sendLock need no longer
protect the journal update.
With parallel journal updates we get the benefit of write batching (sharing an
fsync) for multiple producers on a single destination.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
