Category Archives: General

Yet another one PZEM-004T/ESP8266 energy meter.

This post describes my variant of a system that is able to store and visualize the history of power consumption of a household. System is based on “AC multifunction meter” PZEM-004T and NodeMCU ESP-12F (ESP8266) which transmits data to a remote MySQL database.

Linux, laptop and external HDMI display problem.

Not very nice workaround for a problem on Kubuntu 18.04 laptop when system doesn’t notice that external HDMI display has been disconnected if the speed which user plugs out HDMI cable is less than five speeds of light.

SSD wear and frequent small writes into MySQL DB

For about 2 years I used SSD as a system drive for my home server. It was mounted with noatime attribute and I knew there would be no services which can cause heavy write load on it. But recently I started a project which requires a small amount of data to be written in database each second or two. I guessed that such kind of load would increase ssd’s wear but I was unprepared to face how huge the wear is…