How much time is needed for compiling?

Build-time is highly dependable on the number of Cores/Jobs and can be shrunk to less than 30 minutes (from 90 minutes). Build time with single core can take several hours.

make jobs time needed source
1, typical ?
1, all 10h48min buildbot
2, all, local feed mirrors 3h40min
4, typical 45min
4, all, local feed mirrors 2h17min

Typical: Select packages fitting into 8MB flash, build on HDD, ar71xx or brcm47xx target

FIXME Test SSD vs. HDD