emqtt MAX concurrent client benchmarking problem

[mingdong]

We were trying to benchmarking emqtt broker(mostly interested on getting a number for max concurrent clients it can support). We have followed http://docs.emqtt.com/en/latest/tune.html to tune both the broker and the test clients on AWS. The results we got are far from what we read from emqttd wiki, e.g. for one million concurrent MQTT connections(as well as the only benchmark results for 0.12 release reading from https://github.com/emqtt/emqttd/wiki/benchmark-for-0.12.0-release.) We did not see any error logs on broker, only thing we noticed was that all the test clients started to timeout as shown in the screenshot.

You can see the details of our test setup/configuration, test result from the attached file. emqttd Benchmarking reports - Sheet1.pdf

My question is, What could be the potential bottle neck in our setup? what kind of hardware we need in order to get close-to-advertised concurrent connections? Thank you.

[emqplus]

@mingdong. I have no idea about the problems of your benchmark setup from your report. We usually benchmark the broker on qingcloud.com when a new release is ready. A single 12Core, 32G CentOS node can handle about 1 million concurrent connections.

You could check the statistics of TCP Listeners:

./bin/emqttd_ctl listeners

[SarithaM25]

@mingdong I'm also facing the same issue,can you please share any workaround for that situation if you find any, that will be great help. Thanks.

[arihantdaga]

Same here.. I used this guide and did everything... http://emqtt.io/docs/v2/tune.html

But very strangely the maximum no of connection in my dashboard reaches only upto 3500-3700 and after around 3300 connection number of connection grows very slower and does not exceeds above around 3700. I checked my machine's ram and cpu usage.. they are also very low, so it is not the insufficiency of resources (CPU/Ram) on the server...

Any idea what else needs to be done.. ?