SuoNayi,
I guess what I was trying to elude to was that there is no dispatch
queue per say but just a dispatch count. The queue that the message was
dispatch from is the queue for the message, and the metrics are a
representation of what the broker has done with those messages in the
queue. With that said you are correct in the fact that if consumers are
not acknowledging messages the messages will not get dequeued and the
Broker will maintain the message in the queue causing the memory needed
for the messages to not be released. There are many ways of handling
these scenarios from expiring messages to auto acknowledging.
On 2012-12-23 19:57, SuoNayi wrote:
Thanks chris, in fact I know what these metrics mean.
Here I just want to make sure the consequence of my use case where
my consumer only receives messages but not ack them at all(via the
client acknowledge model).Because the broker need track the messages
that are dispatched to the consumer and not acked by the consumer all
the time so the dispatched queue size keeps increasing.
When lots of messages(supposing there are many pending messages
for dispatch) are dispatched to the consumer the memory consumption
in the broker will exceed the memory limit of the queue at last, the
dispatch
job will pause for waiting for available memory space.
Hope someone can correct my judgement.
Thanks,
SuoNayi
At 2012-12-23 23:46:16,chris.o...@mediadriver.com wrote:
SuoNayi
Queue's only keep one copy of any message at any given time, that
I
am aware of. What you are seeing the web console are metrics that the
Broker maintains about the Queue. Messages arrive to a Queue the
Enqueue
count increments. A Consumer reads a message from the Queue the
Dispatch
count increments. The Consumer acknowledges receipt of the message
the
Dequeue count increments. These are just numbers that correspond to
the
actions that the Broker has taken for a message. Hopefully these help
explain what it is you are seeing.
On 2012-12-23 08:40, SuoNayi wrote:
Hi all,
I just want to make sure what will happen if my consumer uses the
client acknowledge model
but no further explicit acknowledges are made?According to my
observation,when producers are keeping
sending messages to the queue,the dispatched queue size for my
consumer (on the web console)
keeps increasing.
I assume that with the increase of the dispatched queue size, more
and more messages will be
loaded into the dispatched queue for the subscription in the broker
and more memory is taken from the SystemUsage.
When the memory limit is exceed,the dispatch messages to the
consumer
will pause for available memory space.
If the memory usage is not handled properly, OOM will be thrown.
Please correct me if I'm wrong.
Thanks,
SuoNayi
