Is there any way to throttle down CPU load for npm and node_index.js?
After Node-red instalation CPU load for those two services is jumping to 100% every 2 seconds. 
Hi,
you could use tools like cpulimit
https://linoxide.com/linux-how-to/limit-cpu-usage-processes-linux/
Great idea!
…but how low can we go with that, not to effect node-red too much (I use node-red just for two flows, scheduled for 2 seconds time frame per day)?
Are those two services needed just for node-red or also for some other software from dietpi list?
honestly I don’t know. I never used such a tool and usually there is a need for such CPU load. Otherwise the application would not behave like this? I guess you would need to play with it to find fitting values.
ok, I’ll try&report here.
Tnx!
test so far…
root@DietPi:/home/tibo# cpulimit -e node -l 40
Process 31076 detected
Process 31076 dead!
Warning: no target process found. Waiting for it…
Process 31107 detected
Process 31107 dead!
Warning: no target process found. Waiting for it…
Process 31150 detected
Process 31150 dead!
Warning: no target process found. Waiting for it…
Process 31181 detected
Process 31181 dead!
Warning: no target process found. Waiting for it…
Process 31224 detected
Process 31224 dead!
Warning: no target process found. Waiting for it…
it looks like node process changes PID all the time, so cpulimit cannot limit the process only by ID 
that could mean node is crashing all the the time and restarting? Otherwise I could not imagine why it is changing process id again and again
you are right.
that explains CPU load jumping.
but what causes that…
strange…
if dietpi-services stop node-red is executed, node and npm does not stop at all…
you could have a look to journalctl -u node-red
nothing strange there:
Jan 25 22:52:29 DietPi node-red[16635]: 25 Jan 22:52:29 - [info] Stopped flows
Jan 25 22:52:29 DietPi systemd[1]: node-red.service: Succeeded.
Jan 25 22:52:29 DietPi systemd[1]: Stopped Node-RED (DietPi).
npm and node_index.js still high CPU load
that’s all? looks like it is not starting correctly. can you do a reboot and check again
no, i did’t paste everything
Jan 25 23:02:53 DietPi systemd[1]: Started Node-RED (DietPi).
Jan 25 23:03:05 DietPi node-red[1266]: 25 Jan 23:03:05 - [info]
Jan 25 23:03:05 DietPi node-red[1266]: Welcome to Node-RED
Jan 25 23:03:05 DietPi node-red[1266]: ===================
Jan 25 23:03:05 DietPi node-red[1266]: 25 Jan 23:03:05 - [info] Node-RED version: v1.2.7
Jan 25 23:03:05 DietPi node-red[1266]: 25 Jan 23:03:05 - [info] Node.js version: v15.6.0
Jan 25 23:03:05 DietPi node-red[1266]: 25 Jan 23:03:05 - [info] Linux 5.4.83-v7+ arm LE
Jan 25 23:03:10 DietPi node-red[1266]: 25 Jan 23:03:10 - [info] Loading palette nodes
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] Settings file : /mnt/dietpi_userdata/node-red/settings.js
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] Context store : ‘default’ [module=memory]
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] User directory : /mnt/dietpi_userdata/node-red
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [warn] Projects disabled : editorTheme.projects.enabled=false
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] Flows file : /mnt/dietpi_userdata/node-red/flows_DietPi.json
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] Server now running at http://127.0.0.1:1880/
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [warn]
Jan 25 23:03:24 DietPi node-red[1266]: ---------------------------------------------------------------------
Jan 25 23:03:24 DietPi node-red[1266]: Your flow credentials file is encrypted using a system-generated key.
Jan 25 23:03:24 DietPi node-red[1266]: If the system-generated key is lost for any reason, your credentials
Jan 25 23:03:24 DietPi node-red[1266]: file will not be recoverable, you will have to delete it and re-enter
Jan 25 23:03:24 DietPi node-red[1266]: your credentials.
Jan 25 23:03:24 DietPi node-red[1266]: You should set your own key using the ‘credentialSecret’ option in
Jan 25 23:03:24 DietPi node-red[1266]: your settings file. Node-RED will then re-encrypt your credentials
Jan 25 23:03:24 DietPi node-red[1266]: file using your chosen key the next time you deploy a change.
Jan 25 23:03:24 DietPi node-red[1266]: ---------------------------------------------------------------------
Jan 25 23:03:24 DietPi node-red[1266]: 25 Jan 23:03:24 - [info] Starting flows
everythimg seems fine. node-red works perfectly.
should I ignore mentioned issue or do you think that it needs to be investigated further?
after stop node-red:
Jan 25 23:09:24 DietPi node-red[1266]: 25 Jan 23:09:24 - [info] Stopped flows
Jan 25 23:09:24 DietPi systemd[1]: node-red.service: Succeeded.
Jan 25 23:09:24 DietPi systemd[1]: Stopped Node-RED (DietPi).
and starting it again?
temporary fix:
with cron job that keeps those two processes alive just for needed 1 minute per day should be ok? 
this I don’t understood. What should be the aim?
no.
node-red does not keeps restarting
so it is running fine now? No CPU spikes anymore?
I need node-red only for to few flows, all are scheduled for one second before and one second after midnight.
I can keep node-red alive only for those two seconds (or let’s say 1 minute). For RPI’s health 
node-red isn’t restarting, but node and npm processes are CPU spiking
well you could create a script stating node, do a sleep 120 and stop node again. This than to be scheduled on cron