In the OpenBSD FAQ, in the Installation Guide section, it says "OpenBSD can be installed in as little as 512MB, but using a device that small is something for advanced users". https://www.openbsd.org/faq/faq4.html#Partitioning
In fact, the installation of only the kernel and base73.tgz required 629MB for i386 and 1GB for amd64. For example, if I delete the files under /usr/share/relink, I can get within 512MB, but this is not a desirable installation method, is it? ---- Yoshihiro Kawamata https://fuguita.org
