I noticed this interesting phenomenon when testing docker container: when I exec into a container and execute whatever command like echo, cd, cp, rm inside the container, it will cause a small increment of SizeRw (docker inspect --size [container] | grep SizeRw).

I thought it was caused by logging or something, but the problem persisted after I disabled the logging driver with --logging-driver=none, I also tried to clean bash history with history -c with no luck. Can someone explain the root cause behind this? Is this a normal behavior and how to avoid it? BTW the image I’m testing is based on busybox. Thank you in advance.