ARM 64 Bit Server CPU Development Kit • Hacker News Board

Re: ARM 64 Bit Server CPU Development Kit

#11

Post by justizin » Sat, May 31, 2014, 12:15 AM UTC

ChuckMcM wrote: post #6

Interesting, I kind of expected AMD to be first out the gate with one. From : http://www.zdnet.com/applied-micro-canonical-claim-the-first... "The X-Gene is an ARMv8 64-bit Server-on-a-Chip package running at up to 2.4GHz. It combines 10/40 Gigabit mixed signal I/O with what AMCC calls an enterprise-class memory subsystem. Compared to x86 architectures, AMCC claims that it delivers four-times the processor density wh…

That's not necessarily true, you don't need 10G ethernet to most nodes in practice, and you don't typically need dual unless you are trying to run active/passive. smaller footprint nodes like this often are, themselves, the failure unit.

most workloads don't need much storage except on the DB end, app servers and esp things like memcache already are run on large non-x86 tiers. Facebook, notably, uses Tilera machines for memcache last I heard.

A TB of RAM, sure, but it's a bit greedy to say nothing less than that is of much use, when 128GB of RAM in a single machine is a relatively recent advancement.

Also note: these are development kits. This is presumably to begin targeting ARM, make sure your code runs reliably. Anything you can do with a TB of RAM and 32 full speed SATA channels you can develop on 4GB of RAM with one drive, as Every_Linux_Box_Ever has proven.

Re: ARM 64 Bit Server CPU Development Kit

#12

Post by reitzensteinm » Sat, May 31, 2014, 12:41 AM UTC

ChuckMcM wrote: post #6

Interesting, I kind of expected AMD to be first out the gate with one. From : http://www.zdnet.com/applied-micro-canonical-claim-the-first... "The X-Gene is an ARMv8 64-bit Server-on-a-Chip package running at up to 2.4GHz. It combines 10/40 Gigabit mixed signal I/O with what AMCC calls an enterprise-class memory subsystem. Compared to x86 architectures, AMCC claims that it delivers four-times the processor density wh…

These comparisons (from the quote) often come up with ARM vs x86, but they're always comparing apples and oranges. Yes, you can fit an ARM core with 1/4 the performance in, say, 1/16 the power envelope, but you can do that with x86 cores as well.

The cores we've got are still heavily optimized for single thread performance, because that's what the market demands. Even embarrassingly parallel domains like web serving have increased latency, and Amdahl's law is a problem for most real world programs. The penalty paid for this is high, due to diminishing returns due to caches, complex architectures, and (roughly quadratic) power increases due to higher clock speed.

Ignoring the obvious ARM versus Atom low end comparison, Intel is readying Knight's Landing, their 2015 Xeon Phi product. It's going to include 72 Atom cores, with 288 threads, and be able to be socketed in standard Xeon motherboards.

That's 1152 Atom threads on one commodity(ish) server (and the first time I've ever used a calculator to determine the thread count of a server), and it looks a hell of a lot like the picture being painted by many ARM vendors. Many lightweight cores, great power efficiency and peak performance, and most likely not necessarily suited to latency sensitive tasks.

I don't think it's about ARM versus x86 at all, it's more about a new strategy for computation. Intel can't transition its traditional x86 processors over to the new model, so they're starting to make Atom a first class Xeon product (both with low power standard Atom chips already released, and the Xeon Phi).

The market will shift the other way too - we're going to see ARM processors from multiple vendors that rival at least AMD's x86 offerings in terms of performance per core. And power consumption, too.

After that, there'll be products on both ends of the spectrum from both architectures, and then maybe we can start to move past the false dichotomy of ARM having efficiency and x86 having performance.

Re: ARM 64 Bit Server CPU Development Kit

#13

Post by Gracana » Sat, May 31, 2014, 1:55 AM UTC

Well that's far too much money for me to spend, but I am excited to see it.

Can anyone comment on whether or not ARMv8 is beneficial in embedded environments with limited memory? Will we eventually see self-contained ARMv8 microcontrollers?

Re: ARM 64 Bit Server CPU Development Kit

#14

Post by wmf » Sat, May 31, 2014, 2:29 AM UTC

Gracana wrote: post #13

Well that's far too much money for me to spend, but I am excited to see it. Can anyone comment on whether or not ARMv8 is beneficial in embedded environments with limited memory? Will we eventually see self-contained ARMv8 microcontrollers?

ARMv8 is generally faster than ARMv7 although it depends on the program.

Re: ARM 64 Bit Server CPU Development Kit

#15

Post by gonzo » Sat, May 31, 2014, 6:36 AM UTC

reitzensteinm wrote: post #12

ChuckMcM wrote: post #6

Interesting, I kind of expected AMD to be first out the gate with one. From : http://www.zdnet.com/applied-micro-canonical-claim-the-first... "The X-Gene is an ARMv8 64-bit Server-on-a-Chip package running at up to 2.4GHz. It combines 10/40 Gigabit mixed signal I/O with what AMCC calls an enterprise-class memory subsystem. Compared to x86 architectures, AMCC claims that it delivers four-times the processor density wh…

These comparisons (from the quote) often come up with ARM vs x86, but they're always comparing apples and oranges. Yes, you can fit an ARM core with 1/4 the performance in, say, 1/16 the power envelope, but you can do that with x86 cores as well. The cores we've got are still heavily optimized for single thread performance, because that's what the market demands. Even embarrassingly parallel domains like web serving…

Knights Landing will be built using up to 72 Airmont (Atom) cores with four threads per core.

Not 1152 threads, 288. 4 sockets -> 1152 threads.

Re: ARM 64 Bit Server CPU Development Kit

#16

Post by rwmj » Sat, May 31, 2014, 6:45 AM UTC

http://rwmj.wordpress.com/2014/03/04/red-hat-64-bit-arm-deve...

Jon Masters' keynote at Linaro Asia earlier this year. Jon is heading Red Hat's efforts on aarch64. In brief he wants:

- upstream kernels only, single kernel boots on all manufacturers' hardware (no kernel zoo like on ARM 32 bit)

- UEFI + ACPI (no device tree nonsense)

Re: ARM 64 Bit Server CPU Development Kit

#17

Post by reitzensteinm » Sat, May 31, 2014, 7:01 AM UTC

gonzo wrote: post #15

reitzensteinm wrote: post #12

Earlier quoted context omitted.

These comparisons (from the quote) often come up with ARM vs x86, but they're always comparing apples and oranges. Yes, you can fit an ARM core with 1/4 the performance in, say, 1/16 the power envelope, but you can do that with x86 cores as well. The cores we've got are still heavily optimized for single thread performance, because that's what the market demands. Even embarrassingly parallel domains like web serving…

Knights Landing will be built using up to 72 Airmont (Atom) cores with four threads per core. Not 1152 threads, 288. 4 sockets -> 1152 threads.

I think you may have misread, my 1152 figure was per server, not socket.

Re: ARM 64 Bit Server CPU Development Kit

#18

Post by Quequau » Sat, May 31, 2014, 8:15 AM UTC

reitzensteinm wrote: post #12

ChuckMcM wrote: post #6

Interesting, I kind of expected AMD to be first out the gate with one. From : http://www.zdnet.com/applied-micro-canonical-claim-the-first... "The X-Gene is an ARMv8 64-bit Server-on-a-Chip package running at up to 2.4GHz. It combines 10/40 Gigabit mixed signal I/O with what AMCC calls an enterprise-class memory subsystem. Compared to x86 architectures, AMCC claims that it delivers four-times the processor density wh…

These comparisons (from the quote) often come up with ARM vs x86, but they're always comparing apples and oranges. Yes, you can fit an ARM core with 1/4 the performance in, say, 1/16 the power envelope, but you can do that with x86 cores as well. The cores we've got are still heavily optimized for single thread performance, because that's what the market demands. Even embarrassingly parallel domains like web serving…

I'm not sure it's accurate to compare the Knight's Landing, Xeon Phi with ARM 64 in this way. The focus on vector compute capability on the Phi makes it much, much different than just a bunch of Atom cores on one die.

Re: ARM 64 Bit Server CPU Development Kit

#19

Post by Nexxxeh » Sat, May 31, 2014, 8:33 AM UTC

How much is (was) it? When I visit the site, it asks me to register before I can get any further.

Re: ARM 64 Bit Server CPU Development Kit

#20

Post by justincormack » Sat, May 31, 2014, 10:26 AM UTC

Gracana wrote: post #13

Well that's far too much money for me to spend, but I am excited to see it. Can anyone comment on whether or not ARMv8 is beneficial in embedded environments with limited memory? Will we eventually see self-contained ARMv8 microcontrollers?

why do you want a 64 bit microcontroller?