CODE EXAMPLE FOR SHELL

clear pagespeed cache

#1. Determine your cache location in pagespeed.conf (your location may vary from this)
sudo grep -i "filecachepath" /etc/apache2/mods-enabled/pagespeed.conf

# The ModPagespeedFileCachePath directory must exist and be writable
ModPagespeedFileCachePath "/var/cache/mod_pagespeed/"

# 2. Touch the cache.flush file
sudo touch /var/cache/mod_pagespeed/cache.flush

# 3. Restart apache

sudo service apache2 restart