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Comment by Donch | Hacker News Reader

I think this is a highly significant move by ARM. It's amazing when you speak to datacentre people and they tell you how much of your server charges go on electricity and cooling. My recent example was £200 extra/year for an additional Opteron 6128 and £400 extra/year for the increased power usage from that processor!

There is an obvious gap in the market for low power, low heat generating, high memory throughput server processors. I'd just like to see a reference Linux distro which supports 16 ARM cores as well as a reference server card...

The specs:

http://www.calxeda.com/products/energycore/ecx1000/techspecs

only refer to 32-bit memory addressing as well (ie. <4GB of memory). Seems like the wait will be for the ARMv8 64-bit processors to be integrated.

Interesting times!

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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.

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.

The reason hardware support for virtualization is necessary on x86 is only because of some design decisions dating back to the 80286.

Can you elaborate?

http://en.wikipedia.org/wiki/Popek_and_Goldberg_virtualizati...

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.

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.

Perhaps it is time for distributed RDBMS with datastores purely in RAM.

According to http://www.theregister.co.uk/2010/08/25/arm_server_extension... there's an extension for 32-bit ARM processors that allows them to address 40-bit memory (1TB RAM). This before 64-bit processors (that should arrive in 2014) Btw I dont know if this option is available in Calxeda/HP solutions.

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