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Single System Image is some cool tech in this area, where basically you're running a single operating system instance across the network, which sees each comput

Single System Image is some cool tech in this area, where basically you're running a single operating system instance across the network, which sees each computer as just more available computing resources, and you can for example migrate processes from one computer to another. There are also database systems that use a ring of nodes connected with RDMA and optimize for that data layout, creating a sort of merry-go-round of data: http://homepages.cwi.nl/~mk/datacyclotron.pdf http://homepages.cwi.nl/~mk/datacyclotron.pdf

ChuckMcM 9y ago
That is pretty cool, all the dates are place holders, when was it published? Tom Lyon had a startup in this space that was trying to build network accessible memory systems to solve the 'process migration' problem. That is the problem where moving a process on a Linux system takes too long relative to the benefit. Google looked at some proposals that were kinda sorta like this when they were soliciting ideas for their 'energy proportional computing' effort. Basically they were attacking the problem that the difference between an idle machine and a fully loaded machine was about 25% power usage. That isn't held against your PUE (after all the machine is 'running') but it does mean you could theoretically increase your energy efficiency by 50% if you could leave idle machines powered off and effectively bring them on line quickly enough to meet your design goals.
- makmanalp 9y ago
  It seems the paper was published around 2010-2011. This is Martin Kersten, same guy who did MonetDB. I'm not sure if the idea went anywhere since it was very radical and wacky, but perhaps it's waiting for its time to come :-) The neat thing about it isn't that it /can/ work in such an architecture, it's more that it's optimized to leverage it. Their idea is that you can spin data through the ring one way, and spin requests the other way, and you can have a multi-node distributed data system while avoiding a ton of global coordination. > you could theoretically increase your energy efficiency by 50% if you could leave idle machines powered off and effectively bring them on line quickly enough to meet your design goals It's a cool pattern that I keep seeing of people trying similar ideas at different scales! Multicore processors for mobile computers also turn cores on and off to save power, and migrate and balance processes across cores, I believe. Similarly, the process migration thing could be solved at the language level rather than the OS level, which I think is what some erlang stuff does - as long as you have global coordination and can serialize process state and code, why not?
- puzzle 9y ago
  Google ended up using RDMA. The TIMELY paper, unfortunately, does not mention publicly the applications and services taking advantage of it, but the Tensorflow site confirms that it's one of them.

ChuckMcM 9y ago

That is pretty cool, all the dates are place holders, when was it published? Tom Lyon had a startup in this space that was trying to build network accessible memory systems to solve the 'process migration' problem. That is the problem where moving a process on a Linux system takes too long relative to the benefit. Google looked at some proposals that were kinda sorta like this when they were soliciting ideas for their 'energy proportional computing' effort. Basically they were attacking the problem that the difference between an idle machine and a fully loaded machine was about 25% power usage. That isn't held against your PUE (after all the machine is 'running') but it does mean you could theoretically increase your energy efficiency by 50% if you could leave idle machines powered off and effectively bring them on line quickly enough to meet your design goals.

makmanalp 9y ago
It seems the paper was published around 2010-2011. This is Martin Kersten, same guy who did MonetDB. I'm not sure if the idea went anywhere since it was very radical and wacky, but perhaps it's waiting for its time to come :-) The neat thing about it isn't that it /can/ work in such an architecture, it's more that it's optimized to leverage it. Their idea is that you can spin data through the ring one way, and spin requests the other way, and you can have a multi-node distributed data system while avoiding a ton of global coordination. > you could theoretically increase your energy efficiency by 50% if you could leave idle machines powered off and effectively bring them on line quickly enough to meet your design goals It's a cool pattern that I keep seeing of people trying similar ideas at different scales! Multicore processors for mobile computers also turn cores on and off to save power, and migrate and balance processes across cores, I believe. Similarly, the process migration thing could be solved at the language level rather than the OS level, which I think is what some erlang stuff does - as long as you have global coordination and can serialize process state and code, why not?
puzzle 9y ago
Google ended up using RDMA. The TIMELY paper, unfortunately, does not mention publicly the applications and services taking advantage of it, but the Tensorflow site confirms that it's one of them.