I setup a magento store that is in production since a year and half with no issue except this one :
For performance reason i put /var/www/html/var/cache
and /var/www/html/var/session
in a ramdisk using the following code
tmpfs -o size=128m /var/www/html/var/cache tmpfs defaults,uid=apache,gid=apache,mode=755 0 0
tmpfs -o size=128m /var/www/html/var/session tmpfs defaults,uid=apache,gid=apache,mode=755 0 0
With apc and this setup the store is fast enough for us small target.
The problem i have with this setup is following : when i create a new categorie (menu or not), they appear frontend only if cache is dissable in Magento. If i enable again the cache the new categorie dissapear again.
This happen even if i flush the cache before from admin, (the both folder i could watch from fizella become empty) or using *rm -rdf /var/www/html/var/cache/*
in command line
If i reboot the server, everything will work fine i could enable the cache in the admin and the the new categorie create front end. I have a similar issue with the home slider. Except that the store works as normal, new product appear normally frontend with this setup.
If i dissable the ramdisk everything work totally normal, i could create new categorie and they appear immediatly frontend
Seems there is some persistent file in ramdisk even if i flush the cache from admin or using *rm -rdf /var/www/html/var/cache/*
Any idea how totally flush the cache of tmpfs ramdisk partition ? seems there is some persitent cache file in it, until reboot Ramdisk really boost the store on a small server without ssd, so i will be happy to keep it.