qpid-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Alessandro Crotti - SMC Consulting <a.cro...@smcconsulting.it>
Subject Qpid JMS 0.11.0 AMQP 1.0 client - Receiver issue with prefetch > 1
Date Thu, 10 May 2018 13:41:18 GMT

Using Qpid JMS 0.11.0 AMQP 1.0 client, which is the latest version for 
Java 7, we experienced an issue when you set prefetch > 1 and start 
consuming messages from a queue in asynchronous mode, using 
"onMessage()" method and sessionMode = Session.CLIENT_ACKNOWLEDGE.

Taking prefetch= 10 as example, I noticed that:

 1. When you open connection/session/listener, the client sends a "flow"
    performative with linkCredit=10, which is correctly the prefetch
    value. Prefetched messages = 10
 2. The client starts to process the first message received using class
    "MessageDeliverTask" method "run()" (all inside JmsMessageConsumer.java)
 3. There is a call "ackFromReceive(envelope)" at row 667 which,
    following sub-calls, will call method "sendFlowIfNeeded()" of class
 4. in this method "newCredit" is calculated to send a new "flow"
    performative. Here the calculation doesn't check how many prefetched
    messages already are on client side. The currentCredit is 0, for
    this reason is sent a "flow" performative with linkCredit=10.
    Prefetched messages =20
 5. There is a call "messageListener.onMessage(copy);" at row 672 which
    triggers the import of the message. Then the prefetched messages = 19.
 6. The process starts again from point 2 increasing constantly the
    prefetched messages collected on client side, causing timeout issues
    because if they are 1 million of messages, the client can't process
    them before they expire

I compared code of method "sendFlowIfNeeded()" (see point 3) in version 
0.11.0 with the code of version 0.31.0: in version 0.31.0 the code is 
changed and the calculation considers also "prefetchMessageCount".

Is this a known issue? Will you fix it for 0.11.x version because it is 
the latest version for Java 7?

Best Regards

SMC Consulting <http://www.smcconsulting.it>

facebook <http://www.facebook.com/SMC-Consulting-Srl-597548223675024/> 
linkeding <http://www.linkedin.com/company/smc-consulting-srl> 
*Alessandro Crotti*
Senior Developer

tel:  +39 342 573 4450
skype:  crotti.alessandro

*SMC Consulting* <http://www.smcconsulting.it>
Via dell'industria, 87 41012 Carpi (MO) - Italy
tel: +39 059 664875

CONFIDENTIALITY NOTICE: This message may contain confidential and/or 
privileged information.
If you are not the intended recipient, please do not use its contents 
for any purpose, advise
the sender immediately by reply e-mail and delete this message and any 
attachments without retaining a copy.

View raw message