activemq-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jörn Kottmann <kottm...@gmail.com>
Subject Pure Active Master Slave completely hangs when slave throttles
Date Thu, 05 Nov 2009 13:02:08 GMT
Hello,

we have a pure master slave broker (activemq 5.3.0) because we need HA 
messaging
queuing.

The broker has a topic with one subscribe and a queue. The topic
receives xml messages which are written to a database by the subscriber
and afterwards a notification is send to the queue which just contains 
the message id.

I started with the default configuration and only modified it as 
described in
the pure master slave documentation, but the default contains
<policyEntry topic=">" producerFlowControl="true" memoryLimit="1mb">
and
<policyEntry queue=">" producerFlowControl="true" memoryLimit="1mb">,
the small memory limit caused throttling in the slave for the topic, at 
least this log
entry appeared on the slave:

 INFO | Usage Manager memory limit reached for topic://MessageFeed. 
Producers will be throttled to the rate at which messages are removed 
from this destination to prevent flooding it. See 
http://activemq.apache.org/producer-flow-control.html for more info

Afterwards the master was just hanging and dequeuing messages from the topic
or the queue was not possible.

I increased the memory limit but and gave the slave a little more 
memory, but is
that enough to make sure it cannot happen again ? Is there a way that 
the slave can
just fail if something goes wrong and not block the master ?

I also would love to learn how a slave can be re-attached to the master 
in case
the slave machine fails, the documentation only describes what must be done
to recover from a master failure (but maybe I missed something).

Thanks,
Jörn

 


Mime
View raw message