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Remote Direct Memory Access Over IP

Posted by timothy on from the ping-to-break-your-train-of-thought dept.

doormat writes "Accessing another computer's memory over the internet? It might not be that far off. Sounds like a great tool for clustering, especially considering that the new motherboards have gigabit ethernet and a link directly to the northbridge/MCH."

5 of 166 comments (clear)

  1. Also by madcoder47 · · Score: 5, Insightful

    Not to mention easy access to sensitive information in emails, documents, and PIMs that the user currently is running and are resident in memory.

  2. haha... outlook worm writers will have a field day by sisukapalli1 · · Score: 4, Insightful

    Seriously though... this is where Scott McNealy's vision of "The Network is the Computer" comes even closer to reality.

    S

  3. Re:rdma? by astrashe · · Score: 4, Insightful

    You hit the nail on the head -- the security implications of this are staggering.

    And doesn't tcp/ip involve a lot of overhead for memory access?

  4. I smell a hotfix... by fejrskov · · Score: 5, Insightful

    > Microsoft ultimately is expected to support RDMA
    > over TCP/IP in all versions of Windows

    Can you see it coming? The ultimate Windows root exploit!! Hmm... I guess someone has to go tell them. Othervise they won't notice it until it's too late...

    Seriously, how do you dare to enable this kind of access?!?

  5. Bah, old stuff by Erich · · Score: 4, Insightful
    There's lots of research about network shared memory for use in various things.

    It's very interesting that using memory over the network is very much the same problem as cache coherency amongst processors. If you have multiple processors, you don't want to have to go out to the slow memory when the data you want is in your neighbors cache... so perhaps you grab it from the neighbor's cache.

    Similarly, if you have many computers on a network, and you are out of RAM, and your nighbor has extra RAM, you don't want to page out to your slow disk when you can use your neighbor's memory.

    NUMA machines are somewhere in between these two scenarios.

    There are lots of problems: networks aren't very reliable, there's lots of network balancing issues, etc. But it's certainly interesting research, and can be useful for the right application, I guess.

    Disk is slow, though... memory access time is measured in ns, disk access time is in ms... that's a 1,000,000x difference. So paging to someone else's RAM over the network can be more efficient.

    I don't have any good papers handy, but I'm sure you can google for some.

    --

    -- Erich

    Slashdot reader since 1997