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Red Hat & AMD Demo Live VM Migration Across CPU Vendors

Posted by kdawson on from the dude-where's-my-virtualization-business dept.

An anonymous reader notes an Inquirer story reporting on something of a breakthrough in virtual machine management — a demonstration (not yet a product) of migrating a running virtual machine across CPUs from different vendors (video here). "Red Hat and AMD have just done the so called impossible, and demonstrated VM live migration across CPU architectures. Not only that, they have demonstrated it across CPU vendors, potentially commoditizing server processors. This is quite a feat. Only a few months ago during VMworld, Intel and VMware claimed that this was impossible. Judging by an initial response, VMware is quite irked by this KVM accomplishment and they are pointing to stability concerns. This sound like scaremongering to me ... All the interesting controversy aside, cross-vendor migration is [obviously] a good thing for customers because it avoids platform lock-in."

8 of 134 comments (clear)

  1. This is still unreleased test demo's by Beached · · Score: 4, Insightful

    The real beauty of this will come when the system automatically moves VMs to machines in case of hardware problems or when a system is underutilized. It would let you power down servers during non-peak times and save oodles of cash.

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    1. Re:This is still unreleased test demo's by Hercynium · · Score: 3, Insightful

      Well, that kinda *is* the purpose of live VM migration... it's already being done, just not between systems with different processor types.

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    2. Re:This is still unreleased test demo's by TheRaven64 · · Score: 4, Insightful

      They don't seem to have released many details of this. Migrating between x86-with-SSE and x86-without-SSE, for example, is pretty simple - you just need the OS or hypervisor to trap the illegal instruction exception and emulate. Migrating from x86 to x86-64 is pretty easy too - you just don't get any advantages from the 64-bit chip. Going the other way is really hard, and would need the hypervisor to trap the enter-64-bit-mode instruction and emulate everything until the mode was exited (difficult, slow, and probably pointless).

      I read TFA when it first came out and couldn't work out exactly what they were claiming was novel. Migrating between very-slightly-different flavours of x86 is not really that hard. Migrating between ARM and x86 would be incredibly hard - Xen can actually do this with the P2E work (not sure if it ever made it in to trunk), which migrated a VM from real hardware in to QEMU but, again, that's not an ideal solution unless the emulator has traps that userspace can use - for example a Java VM might get a signal after migration, flush its code caches, and re-JIT as x86 code instead of ARM.

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    3. Re:This is still unreleased test demo's by JEB_eWEEK · · Score: 3, Insightful

      Yes, except without requiring identical hardware.

  2. Still x86 only by boner · · Score: 3, Insightful

    Real magic would have been demonstrating a move between ANY processor architecture - Power, SPARC, x86_64 etc..

    Between x86 processors is nice, but not unexpected.

  3. Re:Pfff... by Anonymous Coward · · Score: 3, Insightful

    so easy that you did it yourself three years ago, right?

  4. Re:Um by Korin43 · · Score: 4, Insightful

    Except they're doing it with KVM, which is open source..

  5. Re:Um by abdulla · · Score: 3, Insightful

    Why should it be dumbed down? I don't go reading Biology articles and expect to know everything. That's why there are links to other articles explaining each bit in more detail.