Just a while ago I moved my virtual machine OH2 setup from a small server (HP N40L/8Gb) to a Docker OH2 setup on a Synology DS918+ with 12 Gb of memory. I then slowly started migrating my other virtual machines over. In the process I also created new ones because of the fact that Docker containers are preconfigured so when you need Node Red then… you fire up a Node Red container etc etc.
At this moment I am running about 12 container with on average 35 % processor load and about 4Gb of memory usage.
I started noticing that sometimes my lights would not respond in a timely fashion, sometimes the time between touching the switch and the reaction of the light would be more than 3 seconds. After checking a log for strange things I even replaced my Zwave stick without result.
Yesterday I had a bright moment and turned of the majority of the containers which had a drastic effect on the performance. Things responded much quicker and it looks like I have found the problem.
I am wondering if anybody has any experience with these kind of problems. Is OH2 so power hungry that it is not a good idea to run it as a container on a lightweight host docker installation? Would a separate RPI better?
Not sure about running OH in a Docker container but it does seem that OH is power hungry. There are several post with RPI owners needing help, just to install OH, and finding the solution is to use a good 5v 2.5A power supply.
I run OH on a VM in Docker along side a Mosquitto, InfluxDB, and Grafana container and don’t see any issues. I’ve no experience with Synology but if I had to guess, I would say there is a bottleneck in disk IO which is causing problems with OH. Maybe you need to bump up the number of file handles available (I know people running OH on Mac sometimes run into this) or the like.
For the most part, I doubt the delay is being caused by CPU consumption and RAM is clearly not a problem.
That is more an issue with the RPi being very sensitive to quality of power. Just about anything can cause an RPi with a poor power supply to crash.
I agree but what do you tell someone that claims OH won’t install, but Raspian will? I personally, have never had this issue but others have, or made the claim. Usually in the first couple post it’s advised, check your power supply, after 50+ post the issue is solved. How, by replacing the power supply.
Maybe the doc’s should include 5v 2.5A Quality Power Supply Required!
We have found that purchasing a 2.5A power supply from a reputable retailer will provide you with ample power to run your Raspberry Pi.
I’m not sure it is our job to duplicate this already existing documentation in the OH docs. Of course, were someone to take it upon themselves to submit a PR with this additional content then I’m sure it would be accepted.