setting up a consumer is a little expensive, have a look at using a composite destination so that you can subscribe to all destinations at once. Also, there is a delay between new consumer registration and async dispatch, so waiting a few seconds before unsubscribe is necessary.
http://activemq.apache.org/composite-destinations.html On 28 April 2011 23:41, Josh Carlson <jcarl...@e-dialog.com> wrote: > We are using a shared file system Master/Slave for the broker. Version 5.4.2. > Our clients use the STOMP protocol. We use client acknowledgements and > communicate synchronously with the broker (using receipts). We set prefetch > to 1 in our subscriptions. Our clients iterate over several queues, > subscribing, checking for messages (timeout of 50ms), and if one isn't > available it un-subscribes and goes to the next queue. There are almost > always cases where there are no messages in the queues. We ran into a problem > where our application slowed down to a crawl when we deployed additional > clients and I've narrowed it down to the fact that most of the time when we > subscribed to the queue and then asked if a message was ready it wouldn't be > even though there were messages in the queue. My assumption is that it is > taking some time to dispatch the message. > > Is there some configuration parameters I might want to set to help with this > problem? Or is this type of use just not going to scale? > > Here is some benchmark data. Each test, creates N consumers, but before they > are allowed to start it enqueues 50*N messages for the consumer into *one* > queue. The first set of metrics is for the case where the consumers are > iterating over 6 different queues (even though there is only data in one). > The second set of metrics we ONLY have 1 queue ... in this case the client > only subscribes and un-subscribes once except in the case where a message > 'isn't ready' in that 50ms (in which case it re-subscribes to the same > queue). The metrics capture the entire process. getNextMessage, iterates over > the queues, doing the subscribes/un-subscribes, receipts etc ... > > Note that in the 6 queue case time degrades once you have 100 consumers. In > the other case it degrades after 100 but we never see a Median greater than > 206ms. > > TEST Case 6 Queues ... 5 of which are empty (note that in this first case > since 5 queues are empty one expects at least 250ms to poll those 5 empty > queues). Times are in seconds. > > Number of Consumers 1. Muliple Queues > Min: 0.349334999918938 > Max: 0.368788999971002 > Mean: 0.350222800001502 > Median: 0.349644500005525 > Std Dev: 0.00271797410606451 > Starting test for consumer count 10 > > Number of Consumers 10. Muliple Queues > Min: 0.349282000097446 > Max: 0.394184999982826 > Mean: 0.353602201999165 > Median: 0.352992500003892 > Std Dev: 0.00542072612850504 > Starting test for consumer count 50 > > Number of Consumers 50. Muliple Queues > Min: 0.315161000005901 > Max: 0.425882000010461 > Mean: 0.360078899599938 > Median: 0.359610499988775 > Std Dev: 0.00788422976924438 > Starting test for consumer count 75 > > Number of Consumers 75. Muliple Queues > Min: 0.342441000044346 > Max: 0.66088400001172 > Mean: 0.401721995466513 > Median: 0.396242500049994 > Std Dev: 0.0404559664668615 > Starting test for consumer count 100 > > Number of Consumers 100. Muliple Queues > Min: 0.352722999989055 > Max: 3.99510599998757 > Mean: 0.563622044800525 > Median: 0.494796500017401 > Std Dev: 0.413950797976057 > Starting test for consumer count 300 > > Number of Consumers 300. Muliple Queues > Min: 0.361888999934308 > Max: 5.53048999991734 > Mean: 1.91027370266765 > Median: 1.8000390000525 > Std Dev: 0.489824211293863 > Starting test for consumer count 600 > > Number of Consumers 600. Muliple Queues > Min: 0.335149999940768 > Max: 10.6164910000516 > Mean: 4.52802392866641 > Median: 4.35808100004215 > Std Dev: 0.840368954779232 > Starting test for consumer count 900 > > Number of Consumers 900. Muliple Queues > Min: 0.639438000041991 > Max: 18.2733670000453 > Mean: 8.00563488822206 > Median: 7.6759294999647 > Std Dev: 1.38340937172684 > Starting test for consumer count 1200 > > Number of Consumers 1200. Muliple Queues > Min: 0.474138000048697 > Max: 31.5018520000158 > Mean: 12.8169781057334 > Median: 12.2411614999873 > Std Dev: 2.45701978986895 > Starting test for consumer count 1500 > > Number of Consumers 1500. Muliple Queues > Min: 3.1234959999565 > Max: 48.7995179999853 > Mean: 18.8858608815866 > Median: 17.5380175000173 > Std Dev: 4.1516799330252 > Starting test for consumer count 1800 > > Number of Consumers 1800. Muliple Queues > Min: 4.99818900006358 > Max: 73.2436839999864 > Mean: 27.1358068585671 > Median: 25.4123435000074 > Std Dev: 6.30049000845097 > Starting test for consumer count 2400 > > Number of Consumers 2400. Muliple Queues > Min: 0.319424999994226 > Max: 114.78910699999 > Mean: 46.0846290592237 > Median: 44.3440699999919 > Std Dev: 10.2871979782358 > > TEST Case only 1 queue > > Number of Consumers 1. Only One Queue > Min: 0.0413880000123754 > Max: 0.0445370000088587 > Mean: 0.0416983800008893 > Median: 0.041657000023406 > Std Dev: 0.00042437742781418 > Starting test for consumer count 10 > > Number of Consumers 10. Only One Queue > Min: 0.0409169999184087 > Max: 0.0494429999962449 > Mean: 0.0419903019983321 > Median: 0.0417659999802709 > Std Dev: 0.000839524388489985 > Starting test for consumer count 50 > > Number of Consumers 50. Only One Queue > Min: 0.00652100006118417 > Max: 0.0843779999995604 > Mean: 0.0431237947992515 > Median: 0.0423434999538586 > Std Dev: 0.00470470800328101 > Starting test for consumer count 75 > > Number of Consumers 75. Only One Queue > Min: 0.00334199995268136 > Max: 0.120109000010416 > Mean: 0.0456681223996294 > Median: 0.0435704999836161 > Std Dev: 0.00729394094656864 > Starting test for consumer count 100 > > Number of Consumers 100. Only One Queue > Min: 0.00263900007121265 > Max: 0.206331999972463 > Mean: 0.051723164400761 > Median: 0.0513750000391155 > Std Dev: 0.0225837245735077 > Starting test for consumer count 300 > > Number of Consumers 300. Only One Queue > Min: 0.00258900003973395 > Max: 1.01170199993066 > Mean: 0.138241231733017 > Median: 0.136385999969207 > Std Dev: 0.0863229692434055 > Starting test for consumer count 600 > > Number of Consumers 600. Only One Queue > Min: 0.00214999995660037 > Max: 3.27785699989181 > Mean: 0.274939405133063 > Median: 0.256795499997679 > Std Dev: 0.237695097382708 > Starting test for consumer count 900 > > Number of Consumers 900. Only One Queue > Min: 0.00206800003070384 > Max: 31.7313950000098 > Mean: 0.5553230254 > Median: 0.338199999998324 > Std Dev: 1.14882073602057 > Starting test for consumer count 1200 > > Number of Consumers 1200. Only One Queue > Min: 0.00257100001908839 > Max: 49.8629720000317 > Mean: 0.912980378683317 > Median: 0.393762999970932 > Std Dev: 2.87091387484458 > Starting test for consumer count 1500 > > Number of Consumers 1500. Only One Queue > Min: 0.00201100006233901 > Max: 74.3607440000633 > Mean: 1.19311908142647 > Median: 0.205018000095152 > Std Dev: 4.4037236439348 > Starting test for consumer count 1800 > > Number of Consumers 1800. Only One Queue > Min: 0.00196300004608929 > Max: 84.4792379999999 > Mean: 1.29789674880008 > Median: 0.117239500046707 > Std Dev: 5.19232074252423 > Starting test for consumer count 2400 > > Number of Consumers 2400. Only One Queue > Min: 0.00200599990785122 > Max: 124.155756999971 > Mean: 1.77886690554984 > Median: 0.101840000017546 > Std Dev: 8.38169615533614 > > -- http://blog.garytully.com http://fusesource.com
