I looked at many other questions on here regarding swap space, but none that I found really addressed my particular situation.
I have an Ubuntu 9.10 64-bit server with 32GB of RAM running as a KVM host system. I'm using LVM on top of RAID1.
The "old-school" swap recommendations suggests 2xRAM or 2xRAM+1GB, or even
if MEM < 2GB then SWAP = MEM*2 else SWAP = MEM+2GB. But I just can't see allocating 66GB of disk space for swap, that seems crazy! I'm thinking 4GB or maybe 8GB would be plenty.
This system is going to be running a number of KVM virtual servers. How does swap work in this situation? Should I have a swap partition for the host server, and then each virtual server gets its own LVM root and LVM swap partition? Or do the virtual servers share the host's swap?