I have a vps and it doesn't have /tmp and /dev/shm in /etc/fstab none /dev/pts devpts rw 0 0 How to create /tmp and /dev/shm ?
In general vps providers won't allow to enable access for external partitions . May be you can use Xen vps , so you can create any type of partitions in xen full virtualization
If you have a fully managed VPS, you can contact your hosting provider and ask them to solve the problem for you.