[ https://issues.apache.org/jira/browse/QPID-8546?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Alex Rudyy resolved QPID-8546. ------------------------------ Resolution: Fixed > [Broker-J] Consumer falling behind producer in the BDB HA clusters > ------------------------------------------------------------------ > > Key: QPID-8546 > URL: https://issues.apache.org/jira/browse/QPID-8546 > Project: Qpid > Issue Type: Bug > Components: Broker-J > Affects Versions: qpid-java-broker-8.0.5 > Reporter: Dedeepya > Priority: Major > Fix For: qpid-java-broker-8.0.6 > > > With current Qpid Broker versions (up to 8.0.4 including) when BDB HA cluster > is distributed across different DCs, a consumer throughput falls > significantly behind the producer . As result, the total system throughput > (determined by the consumer) can be very low. > Such behavior is caused by implementation specifics of BDB message store: > * BDB HA transactions are synchronous for the majority of the nodes. (The > messaging transaction is committed when majority of the nodes in the cluster > acknowledge the transaction on their side) > * The deletion of dequeued messages from the store is synchronous and > impacted by the DC latency. > * 2 separate underlying store transactions are used to delete each > individual message data. Thus, if message consumption happens in > transactional batches of N, the messages are dequeued from the queue in the > transacted batch of N messages. However, after message dequeuing, the > unreferenced message data is deleted using its own store transactions (one > for content and another for metadata). As result for a batch of N, the store > runs 1 + N*2 transactions. The N*2 transactions are synchronous and executed > one after another. If a latency between data centers is high, it adds a > corresponding delay to each store transaction. As result, the message removal > takes time. Only after deletion of N messages, the broker sends commit > confirmation to the client. The message enqueing works differently. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@qpid.apache.org For additional commands, e-mail: dev-h...@qpid.apache.org