I recently made a node-red dashboard that is running on an oracle VM. I can access the dashboard via the internet from any other device. it works well on all devices except 1. I have a tablet PC running ubuntu and when I open the dashboard on chromium, it gets very slow and I get a message saying the page is unresponsive and I can see chromium using a lot of CPU. On the same device it works fine when I use firefox, but on firefox I can't scroll down using the touch screen for some reason.
Does anyone have any Idea what the dashboard is struggling on chromium specifically or why I cant scroll down using the touch screen in firefox?
Sounds as though there is a bug which affects the particular version of Chromium on that tablet. I assume its all up to date, but not on any beta/alpha builds of Chromium?
Are you able to open the page long enough to get onto the developer/inspection screen? (Right click and inspect, or press F12). If so, you can check the console tab and see if there are any warnings.
I'd also be tempted to setup a blank dashboard, with just a some text on it and open that, see if you have the same issues, or its a particular ui-node causing a problem.
I have struggled using other browsers for the NR dashboard, but never put much time into them so can't comment on that.
I also tried to setup a blank dashboard and it worked fine with the simple dashboard. so It must be something in my dashboard that is causing it. I'm guessing its the charts since I read they can cause problems sometimes.
That coupled with running a desktop with Chromium and Dashboard on the Pi where you are running Node-RED is causing the Pi to be very slow. If you check top/htop you will likely see that CPU is very high and quite possibly SWAP usage.
You will get much better performance by getting rid of the desktop on the Pi and accessing dashboard from a different device.
Also take a look at your charts and work out how many points you are asking it to plot on each chart. If the is significantly more than the number of pixels available to your desktop, you know you have a problem. If it is a high res desktop, you could have a problem anyway of course. The charts used in Dashboard are notorious for this issue.
As TI said, the charts can be very heavy, particularly the line charts.
I did some testing on a Pi3 a while ago as we were suffering from running out of memory on a number of Pi's over time, and found that over about 300 points it started struggling, but it handled multiple charts with slightly fewer points quite well. Our higher spec Pi4's perform quite well, so its likely to be the tablet at fault.
I fixed the problem by installing and using proper chrome rather than chromium.
Its not just the CPU load since it was running on a i5 device and I got the same problem when I accessed the dashboard running on another device. It must be something to do with chromium itself. Thanks again.
