font regression build regression

[Graham Percival]

Has anybody else seen a huge slow-down in building fonts?  They
used to whiz by on my screen in a minute or so, but now it takes
about 10 minutes, and more to the point, it involves a massive
amount of disk activity.  My core2quad desktop couldn't play an
mp3 file while building fonts with -j3 !

Might it be building the same font multiple times (with different
threads creating and deleting the same temporary files?), or are
we generating fonts at twice the resolution of the previous one,
or...?

It's been a few weeks since I tried building stuff from scratch,
which leaves a large window of work on the build system and fonts.

- Graham