insert should be smalltile
insert should be smalltile

Joins can get very wide (eg. consider joining a set of tiles horizontally
to make a large image), we don't want mem use to grow as O(N**2). SMALLTILE
will guarantee we keep small and local.

leiyangyou/libvips,lovell/libvips,jcupitt/libvips,mcanthony/libvips,leiyangyou/libvips,leiyangyou/libvips,mcanthony/libvips,lovell/libvips,wishabi/libvips,leiyangyou/libvips,mcanthony/libvips,lovell/libvips,wishabi/libvips,jcupitt/libvips,jcupitt/libvips,wishabi/libvips,mcanthony/libvips,wishabi/libvips,jcupitt/libvips,lovell/libvips