Transcendent Memory: Not Just for Virtualization Anymore!
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. We will describe why RAM is no longer cheap, explain the basics of Transcendent Memory including the kernel changes, and show how tmem can provide unprecedented flexibility toward optimizing RAM utilization in future data centers.
Avi is currently the Principal Program Manager for Oracle Linux. He has spoken at a number of previous linux.conf.au on a range of topics including Asterisk, Puppet and btrfs.
Avi has been working in the Information Systems industry since 1993. He has extensive experience in networking, including server and workstation hardware; network, server and workstation operating systems; and LAN & WAN connectivity. His roles and responsibilities in several projects have included technical project management, network architecture design, network and software integration design, workstation environment development, software deployment and troubleshooting.