I wonder have you tried calling IMessage.Acknowledge()?
On 9/22/06, Rob Lugt <[EMAIL PROTECTED]> wrote:
Quick update to my earlier message. I did eventually find the overload on IConnection.CreateSession() to pass an AcknowledgementMode. I tried setting this to either AutoAcknowledge or DupsOkAcknowledge, but neither had an affect on the apparent throttling of the consumer. ~Rob Rob Lugt wrote: > > Hi James, thanks for the quick reply. > > Yes, I'm using NMS and C# for the client. I wasn't specifying any > particular acknowledgement mode, so my previous tests would have been > using the default - but your question prompted me to try a few things out. > > I found this article which describes acknowledgement modes for consumers: > http://www.activemq.org/site/activemq-performance-module-users-manual.html > > I couldn't find a way to directly manipulate the consumer acknowledgement > mode using the NMS classes (if there is a way please tell me), so I used > the URI syntax on the GetTopic() method e.g. > > IDestination destination = > session.GetTopic("PROD.PRICES.LIVE.IBM_LN?consumer.sessAckMode=autoAck"); > > Sorry, I don't know if I've got the syntax right, but it didn't make any > difference to the tests. I also tried the value "dupsAck" because I read > somewhere that this could improve performance but it also didn't have any > affect. > > The listener is async (delegate added to consumer.Listener) - and is very > light-weight. I checked the CPU and memory activity on the client and the > server and both were comfortably under utilised. > > Best regards > Rob Lugt > > > James.Strachan wrote: >> >> This sounds like it could be related to acknowledgements - you're >> using NMS and C# as the client right? What acknowledgement mode are >> you using and are you using the async or sync listener? >> >> On 9/22/06, Rob Lugt <[EMAIL PROTECTED]> wrote: >>> >>> Hi >>> >>> I'm hoping to use AMQ for a stock price publishing system, so high >>> throughput and low latency are important factors. To verify that the >>> kind >>> of throughput we are after is achievable I've created a very simple >>> producer/consumer pair based on the sample code in >>> http://www.activemq.org/site/nms.html. >>> >>> I've come across a potential problem where the consumer's receive rate >>> dramatically falls after the number of enqueued messages exceeds a >>> certain >>> threshold. I'm pretty sure I must be falling foul of a configuration >>> problem because the number 1000 seems to be significant. >>> >>> If the publisher sends 1000 messages, the consumer happilly receives >>> them in >>> a couple fo seconds. But, if I configure the publisher to send 1500 >>> messages >>> in quick succession, I see a perculiar pattern: the consumer receives >>> the >>> first 300 messages quickly, it then receives the next 200 messages very >>> slowly (approx 5 msgs/s) until there are exactly 1000 messages left in >>> the >>> queue and then it speeds through the last 1000 in just 2 seconds. If I >>> increase the number of messages sent, the same pattern remains i.e. the >>> consumer runs slowly until only 1000 messages remain then speeds up! >>> >>> Topology: >>> Client 1 and Client 2 both running on a single workstation, connecting >>> via >>> OpenWire using NMS >>> AMQ 4.0.1 Broker running on separate machine (Windows 2003 Server, >>> J2SE >>> 1.5.0_06) >>> >>> Client 1 opens a session and publishes n (non-persistent) messages to a >>> single topic. >>> Client 2 opens a session and registers a listener on the same topic. >>> >>> I've tried various options to overcome this, none of which seem to have >>> had >>> any impact. >>> On connection uri I have: >>> jms.useAsyncSend=true&consumer.dispatchAsync=false >>> On Topic name I have: jms.useAsyncSend=true&consumer.dispatchAsync=false >>> >>> Any ideas/solutions gratefully received. >>> >>> Best regards >>> Rob Lugt >>> >>> >>> >>> -- >>> View this message in context: >>> http://www.nabble.com/Topic-consumer-appears-throttled-tf2318926.html#a6451007 >>> Sent from the ActiveMQ - User mailing list archive at Nabble.com. >>> >>> >> >> >> -- >> >> James >> ------- >> http://radio.weblogs.com/0112098/ >> >> > > -- View this message in context: http://www.nabble.com/Topic-consumer-appears-throttled-tf2318926.html#a6455875 Sent from the ActiveMQ - User mailing list archive at Nabble.com.
-- James ------- http://radio.weblogs.com/0112098/
