Maybe I am wrong, but most of older threads weren’t that informative for me, so there is a new one.
I decided to switch my home from FHEM to HA. While nothing out there can beat FHEM for back-end side, once you get to know FHEM ways. Amount of supported devices and other stuff is unbeatable, but look and feel…it lacks ) And FHEM wasn’t never “my thing”, and I am tired of google-translating German. I just went with with FHEM back in time due to hardware I had to support.
But what I found that with HA (I run dev version) there are some noticeable lags, when it is running on rpi3+. Maybe tiny, but still. Things like when you press button, light comes 0.6-0.8 sec after, which pisses me off. Latencies with FHEM were smaller. And I clearly see that most of latency comes from HA (trigger comes from MQTT and action goes to MQTT, so timing MQTT show that there is about 0.4-0.5 sec between trigger and action)
I still want to go with HA, but now I consider dedicated mini-PC, industrial style more or less, from aliexpress, not NUC. And I am trying to figure out, which one to choose (i.e. which CPU). For RAM/SSD my choice is 8GB/128GB. Just to have an option fo future. But with CPU I don’t want overkill in terms of power consumption, heat and costs.
So, this box will run HA, node-red, zigbee2mqtt, FHEM (I still have to keep it to properly support my MAX! heating stuff, homegear/HA combo isn’t there yet, so I export things through MQTT for HA for basic support, and advanced stuff will stay in FHEM), mosquitto, otmonitor, and home-grown piece of software for boiler setpoint calculation depending on the bunch of data. It also will act as wifi AP for dedicated WiFi network for wi-fi home automation devices.
In terms of devices, mostly it is light (about 50 zigbee devices, ±) and heating (20-25 related devices), plus some other stuff. Also all things like homekit and alexa integration.
Currently with my test-setup (not much devices yet) HA consumes approximately 20% of CPU on rpi3+ on 5 minute averages. But unsteady, if you look with higher discretisation (like 0.2-0.3 sec) then it varies between 0 and 90%.
I also want to be ready for future grow, more on sensors side (more occupancy, doors etc), and on control (door locks, curtains etc), maybe cameras, and more exotic stuff.
Currently, for both, FHEM and HA, influxdb and mysql data goes to my home server, where I have mysql and influxdb servers, but I am considering to move HA-related data to the HA host, once it gets more powerful. At least mysql/mariadb. InfluxDB will inevitably produce time to time heavy pressure on the memory, especially if you want to keep lot of data and for long, so I am unconvinced yet.
SO, this is use-case picture.
Now, question which CPU will be good enough for me to reduce latencies and not overkill at the same time.
J1900? J3455? i3-6100U/7100U ? i5-6200U/7200U? Something else?