Why kernel.org is slow

Why kernel.org is slow

If the problem is linked to read/write access and locks, would it be good (when there is a lot of read and few writes like for the Linux versions), to keep the filesystem mounted read-only most of the time?
I mean, keep the partition containing data read-only, then to update do:
mount -o remount,rw /server/data
cp -ra new_linux_version /server/data
sync
mount -o remount,ro /server/data

Just curious,
Etienne.