Horas and konnichiwa untuk semua

I have been having this strange problem that decreases productivity and increases stress level: the MacBook Pro would start up with a little less than 1GB of free disk space, instead of the usual 2GB to 3GB, and then it gradually decreases as I use the MBP, and then it will quickly comes to about zero free disk space and I have to reboot.

I am not sure what did I install that causes this, but before this memory has been a problem too. So I browsed around and found out that extra RAM for MBP is not as expensive as I thought (yes, I have been ignorant). I then upgraded the MBP from 2GB of RAM to 4GB, an increase of 2GB, and voila, MBP suddenly starts with 2.7GB of free disk space! I didn’t delete files, so it seems that MBP has been paging or doing something similar that uses around 2GB of disk space from the start. Now with 4GB of RAM, it does no longer need to do that, so I don’t only have more memory available but also more free disk space.