@fogmania @ykarami Good news to all of you, we have figured out what is causing the slowness and fixed it. It’s been a longer story [ref] - thanks again to @Quazz for doing lots of testing and finding very helpful stuff to figure this out!
As we have not had enough time to push for a new release yet you can simply update to the latest kernel and inits like this:
sudo -i cd /var/www/fog/service/ipxe mv bzImage bzImage.orig wget https://fogproject.org/kernels/bzImage mv bzImage32 bzImage32.orig wget https://fogproject.org/kernels/bzImage32 mv init.xz init.xz.orig wget https://fogproject.org/inits/init.xz mv init_32.xz init_32.xz.orig wget https://fogproject.org/inits/init_32.xz