I've only just installed Node RED and I'm looking for a bit of direction for my project I've created an application for my companies tracking devices that send cell tower and GPS data over mqtt and I was looking to load test it with hundreds of JSON messages a second!!, is this even feasible with …

Hi @Hoboclown , welcome to the forum [image] Hoboclown: load test it with hundreds of JSON messages a second!!, is this even feasible with Node RED?? load testing is certainly possible and "hundreds" of JSON messages should be achievable (though it will depend on how you have written flows an…

If you just want to send the same message repeatedly at that rate then you can do that with an inject node with an appropriate repeat interval set.

Thanks for the quick reply. I've only tried a single message so far from a flow I found in the cookbook. So, the real world scenario is, we have nearly 1000 "tags" that dial in every 5 - 15 seconds with all the cell towers they can "see" from 1-15 along with a GPS coordinate, if available, and any…

Start by building a flow that creates a single message of the type that you need, with appropriate variable data.

Thanks Colin, I have a working flow that starts with an Inject button press, which generates a JSON object using a javascrip function and sends out the message to my MQTT broker with an mqqt out node and listens for the responce with an mqtt in node. I can just copy paste the javascript function a…

[image] Hoboclown: I can just copy paste the javascript function and mqtt nodes to run off the one inject node but that seems rather over kill especially if i need several hundred!! Indeed. You can send more than one msg from a function. Use node.send or return an array. I would likely con…

Like this: [chrome_ShkQqvU2nB] Demo Flow (use CTRL-I to import) [{"id":"1a5423c1ce9beffa","type":"inject","z":"1791a7bd576b3a15","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"5","payloadType":"num","x":1150…

I see where your thinking is going though. many thnaks

for small flows, it is better to paste the JSON export into a code block: ``` type or paste code here ``` NOTE also, in your function, you are stringifying the JS Object before sending it to MQTT node. There is no need to do that (the MQTT node takes care of it)

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Load test with hundreds of JSON messages

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Hoboclown 4 June 2025 17:16 9

MQTT_Simulator.json (6.6 KB)

this is what i have so far

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Load test with hundreds of JSON messages

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