Learn why RAM is no longer cheap, get the basics of Transcendent Memory including the kernel changes, and see how tmem can provide unprecedented flexibility toward optimizing RAM utilization in future data centers.

Delivered at linux.conf.au 2013

30 January 2013: Canberra, ACT

RAM is “cheap”. Or is it?

If a million machine data center could cut RAM in half, how much could be saved, in capital equipment cost and power/cooling expense? Transcendent Memory (or “tmem”) is a new approach for flexibly, dynamically, and efficiently managing physical memory. First conceived to facilitate the optimization of physical memory utilization among a set of guests in a virtualization environment (and implemented in Xen 4.0), tmem has now also been applied in the kernel to dynamically compress page cache and swap pages (“zcache”), and to dynamically hot-plug memory among a set of kernels (“RAMster”).

And tmem may, in the future, allow more effective utilization of future memory-extension technologies. All this with very minimal changes to the kernel required.