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by ajross 5347 days ago
No virtualization ability. No addressibility of more than 4G is a killer for some apps. CPU horsepower density isn't quite as high as they say: at 72 quad-core A9's per rack unit vs. 6.4 Xeons in a comparable 10U blade server. A Nehalem clocks about 3x faster and runs about 1.5-2x faster per clock than the A9 for "random server logic" workloads, so this appears to be higher by only a little bit.

Power consumption isn't clear. I see no peak load wattage numbers, which worries me for a product marketed expressly as a low-power option.

One advantage this architecture does have is density of memory bandwidth. They have 72 DDR3 channels per rack unit vs. 25.6 for a blade server filled with 4-channel Westmere EXs (the Intel boards will stack the DIMMs up on the same channel). So you might want to look seriously at it as a hosting platform for a very parallel in-memory data store.
2 comments
lgeek 5346 days ago
I'm going to guess that by 'no virtualization ability', you probably mean no hardware acceleration for virtualization. That doesn't mean you can't have OS-level virtualization. In fact, I'm working on a hypervisor for BeagleBoard.

Plus, TrustZone has been hacked in the past to implement virtualization.

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yuhong 5346 days ago
The reason hardware support for virtualization is necessary on x86 is only because of some design decisions dating back to the 80286.
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smithian 5346 days ago
Can you elaborate?
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wmf 5346 days ago
http://en.wikipedia.org/wiki/Popek_and_Goldberg_virtualizati...
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ajross 5346 days ago
Last I remember reading ARMv7 wasn't Popek/Goldberg valid. The Cortex-A15 is touted as adding this facility, no? Regardless, a 4G box is going to be a poor resource allocation environment for virtualized hosting, which is something closer to my point.
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lgeek 5345 days ago
Yes, not all ARMv7 instructions meet the Popek/Goldberg virtualization criteria. The project I'm working on uses dynamic binary translation to trap & interpret these instructions. This is how VMware works without virtualization extensions on x86.
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sliverstorm 5346 days ago
Perhaps it is time for distributed RDBMS with datastores purely in RAM.
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