How fast is Node-Red?

Node-red is just fine at that level. I've done a few stress tests on my setup with a few hundred messages coming in from a 500k CAN bus, doing a few simple floating point math ops on them, and then sending an MQTT message. A Pi 3 was fine with this and a Pi4 doesn't breath hard, either.

When I introduced InfluxDB I did a few tests and it just can't handle it. CPU pegs, everything grinds to a halt. It's not the right DB, IMHO. I found it would handle about 50 writes per second without going nuts. I've pared it down to about 5/second now, sanity returned. I don't think there's a great way to store such high resolution data on something like a Pi unless you right it up with an SSD and a real database.

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I suspect that it would be a lot better with just a decent SSD. The problem with the Pi is that, until you move to a Pi4, the I/O speed is really quite limited. In addition, limited memory really kills off performance for high-speed writes.

I've recently connected an SSD (6Gbps) to a RPi-4B via one of its USB 3.0 ports.
I used a powered enclosure for the SSD so it all looks neat and tidy and doesn't put a strain on the Pi's PSU.
Also used the following suggestion so once the Pi has booted (off of the SD card) it uses the SSD.

SD to SSD

Although I've not done any speed tests yet the Pi seems very responsive.

When can we expect some? :wink:

Is there a set of (standard) tests that you or others use?
If so, have you a link or details?

Yes, the Pi4 has an updated controlled which gives much higher throughput.

I've ordered another RPi-4B today, so I can do some 'before' and 'after' speed tests.

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That's called the "I've spent the money - it must be going faster " effect :slight_smile:

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@dceejay Dave, would disabling a debug node be as effective as removing it?

not quite - as the message still gets cloned by the sending node, before then being discarded (before being sent to the websocket). This assumes by disable you mean the button to the right of the node...
Or did you mean disable by the button at the bottom ? (Though I think the same is true - it is still "wired in" - so the clone happens even if the subsequent disabled node then drops it... - but I'd need to dig into the code to check)

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I was wondering about the button at the bottom. Just a curiosity question in case you knew off hand,

The answer will be in the source... the Node.js file probably... but about to engage with real world so will leave it to you

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Hi Folks. I have been away on vacation.

Yes, it is guaranteed.

No, it settles back to "normal".

Hrmm. Interesting. I would also know about disabling with button at the bottom.