Disabling impossible. Removing/Uninstalling mod-pagespeed

The below alone will disable Google mod-pagespeed apache module only temporarily:

sudo a2dismod pagespeed
sudo apachectl configtest
sudo apachectl graceful

For some reason we have seen it enabled back sometime after we run the above. You will need to actually uninstall it. Here is how if you installed it from the debian package in Ubuntu:

sudo sh -c \
  'dpkg -r mod-pagespeed-stable \
  && rm -f /etc/apache2/mods-available/pagespeed* \
  && service apache2 restart'