Influxdb was working but now uses 95% resources

Welcome & Getting Started
1

I’ve been starting to learn Influxdb (1.8.4) over the last few weeks. I have some data coming into Influx from Node Red and visualized with Grafana. Originally all was working well, but recently I’ve started to see my lowly RPi1 lock up after a few minutes consistently. I checked usage prior to one of these crashes and found that influxdb is using massive resources (typically 95% CPU) prior to lock.

If I move the SD over to my RPi3, I can disable Influxdb.service. When moved back to the RPi1 the system seems stable and no significant resource usage (as is expected). It sounds like queries can kill Influx pretty quickly, but I don’t think there should be any running since NR and Grafana are both disabled at this point.

I can remove and reinstall Influxdb to fix it, but not knowing what caused the issue that seems like a poor choice. I would likely have the issue again. The only thing I can think could have caused this issue is a recent update/upgrade I performed in Buster. It could be related or just coincidence though.

I’d appreciate any suggestions on what to check since I’m at a loss after reviewing as many threads and documents as seemed applicable without resolution.

2

My complete guess is that since you’ve been running this system “over the last
few weeks”, you’re running into background tasks where InfluxDB is enforcing
the data retention policy, and consuming resources on what is a pretty low-
resource system to start with (RPi1) as it tries to delete the old data.

Antony.

3

That sounds like a reasonable assumption. Is there a way to view such tasks so I can potentially stop them? If I launch the service it will lock up pretty quickly so it would be better to stop them prior to launching. I could potentially move the repair task to the RPi3 which seems to be a little happier. When I did htop over there, it claimed over 70% usage but the system was still fairly snappy as opposed to the RPi1 which was like dialup!

4

I don’t know what the issue is, but now I can’t even load the SD on the RPi3. I don’t think it’s degraded hardware or SD media, but I certainly look stuck. I’ll try reinstalling the system and hopefully can restore what I backed up without inducing the same issue again.