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Is Intel within ARM’s reach? Pedestrian Detection shows the way

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Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#21

Post by ranjithparakkal »

drill_sarge wrote: post #17
haricm wrote: post #14

Earlier quoted context omitted.

Drill, I partly agree with you. But as you know ARM is getting into servers in a big way. The idea is low power servers(green servers as it is called) of course, and there are several silicon vendors already working on it. ARM recently announced Cortex-A57 and A53 precisely for this segment. The A57 can be expected to have a similar performance to that of A15, but with higher clocks. Hence this discussion, I believe,…

It's not exclusively about the architecture (granted fully fledged x86 out-of-order cpus have some junk to carry around but the architecture overhead isn't that big). The assumption that always is made ARM = low power is just not true. At least not in all scenarios. Nobody expects a typical workstation x86 grade cpu to be competing with a designed for mobile arm-chip. But it's not about architecture, just look at the…

Drill,

The thing is that ARM licenses its core, while Intel doesnt. ARM allows many many silicon vendors to do their own thing. Make their own server CPUs etc. Something they had never been able to do before.

I have no doubt that Intel will get competitive over time on the power front, if they are not already there yet. But people need to know that ARM is getting competitive on the performance front too. So that many silicon vendors, not just Intel, can come out with servers, and SOCs for other types of applications which is pure x86 right now.

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#22

Post by drill_sarge »

devx wrote: post #20

Intel will be in a lot of trouble soon (within 2-3 years). Forget the Core line chips. That's irrelevant. It will remain a cash cow for the next few years, but a rapidly shrinking cash cow nonetheless. They'll move upmarket with them, until there's nowhere to move to. ARM chips' improvements over the next years will make them "good enough" for most people, and Intel's Core chips which cost 10x more (literally) will b…

If a company has enough resources (financial and know-how) to pull out the hammer when needed, it's probably Intel. They have the best people, the best manufacturing, the most experience etc. Just look how they evolved shitty Atom processors in something competitive (bail trail). Intel has a long breath. And once they made arm processors too.

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#23

Post by ranjithparakkal »

Scaevolus wrote: post #12
drill_sarge wrote: post #4

I am getting tired of this whole dumb x86 vs. arm comparison bullshit. You cannot compare chips (read: chips not even talking about architecture here because it's not relevant) which are designed for complete different purposes (high performance big ooo workstation cpu vs. low power mobile chip). Please stop making those.

People always focus on the instruction set -- "ARM's fixed length instructions are easy to decode, so it will win in the long run" -- ignoring how decoding is a tiny fraction of a CPU's silicon and power budget. Memory controllers, pipelining, and efficient superscalar instruction dispatch have far more effect, and Intel has a large lead on ARM in these areas.

"Memory controllers, pipelining, and efficient superscalar instruction dispatch have far more effect"

Memory controllers(atleast the SOC(chip) level ones) are normally developed by the silicon vendor - like Nvidia, Broadcomm, Qualcomm, Samsung, TI, Freescale etc. Not ARM. And these companies have been working on it for many years. They have had graphics, video acceleration, display, camera-interface IPs all integrated into one SOC for almost a decade now. Intel is infact relatively new to this kind of integration.

In anycase everything including memory controllers, pipelining and superscalar has already been taken into account in this benchmark.

What has been left out is higher clocks and hyperthreading. Two things that ARM doesnt have yet.

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#24

Post by mattst88 »

haricm wrote: post #11
vrodic wrote: post #5

In addition to what zurn said, they also don't specify the exact Core i3 model number (it could be an older generation), the RAM speed, and if the data set fits in cache. If RAM access is needed ARM machines usually fall behind quickly, since they usually have much lower RAM bandwidth.

The model number used for the evaluation is Core™ i3-530

That's a Westmere from Jan 2010. Westmere -> Sandy Bridge -> Ivy Bridge -> Haswell.

Comparing with something from 3.5 years and 3 generations ago is useful?

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#25

Post by jwise0 »

Sigh. Although some of this is Intel's own doing, "i3" is not a meaningful descriptor, especially when compared to "Cortex-A15" or "Cortex-A9". "Core i3" can refer to many, many generations of CPUs; this is not a nitpick, but a real complaint, because each of those CPUs have very different performance characteristics. Core i3 has been a Westmere (Nehalem tick); a Sandy Bridge; an Ivy Bridge (Sandy Bridge tick); and a Haswell. Saying "a 1.2GHz Core i3" is about as valuable, then, as saying "a Tegra" -- which could be an ARM11 MPCore (Tegra 6xx); a Cortex-A9 without NEON (Tegra 2); a Cortex-A9 with NEON (Tegra 3); or a Cortex-A15 (Tegra 4).

So, on a micro-level, the comparison is not terribly valid. On a macro-level -- saying that the devices are within an order of magnitude -- the results are reasonable, but certainly not novel...

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#26

Post by [deleted] »

jwise0 wrote: post #25

Sigh. Although some of this is Intel's own doing, "i3" is not a meaningful descriptor, especially when compared to "Cortex-A15" or "Cortex-A9". "Core i3" can refer to many, many generations of CPUs; this is not a nitpick, but a real complaint, because each of those CPUs have very different performance characteristics. Core i3 has been a Westmere (Nehalem tick); a Sandy Bridge; an Ivy Bridge (Sandy Bridge tick); and a…

[deleted]

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#27

Post by [deleted] »

berkut wrote: post #18
zurn wrote: post #3

Spoiler: no. 1265 ms vs 439 ms on their OpenCV benchmark. (Then they play some what-if games by underlocking the i3 in imaginative ways and applying SIMD opts to only the ARM side)

This. Assuming the compiler will generate good SSE code for the Intel CPU is a joke. If you write intrinsics for one arch, write it for both. I'd bet money the Intel side could be made 2.5-3x faster with proper SSE intrinsics and maybe 5-6x faster with a Haswell i3 using AVX (SandyBridge doesn't have the cache bandwidth to fully utilise AVX properly).

[deleted]

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#28

Post by ranjithparakkal »

acqq wrote: post #8
zurn wrote: post #3

Spoiler: no. 1265 ms vs 439 ms on their OpenCV benchmark. (Then they play some what-if games by underlocking the i3 in imaginative ways and applying SIMD opts to only the ARM side)

Very primitive benchmark, not measuring power consumption in comparison between desktop i3 and ARM when the target is embedded use! It would be informative having the power used to process the same tasks compared. So what was the power consumption in every reported run? What was when the i3 was underclocked?

We dont report power because we dont have a way to measure power accurately.

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#29

Post by baq »

haricm wrote: post #13
zurn wrote: post #3

Spoiler: no. 1265 ms vs 439 ms on their OpenCV benchmark. (Then they play some what-if games by underlocking the i3 in imaginative ways and applying SIMD opts to only the ARM side)

We wanted to keep the clocks out of the picture. This I must admit, is a little unfair, because having the ability to run at higher clocks is indeed a capability of the CPU, which cannot be discounted. In this case I compared a Cortex-A15 Vs an Core i3. The A15s can run at max 2GHz I think. While the Core i3 cores can run upto 3GHz. However ARM has Cortex A57 coming along, which I believe will have similar performanc…

i guess nobody really cares about clocks. what people care about is either maximum performance or max performance per watt (cpu and/or whole system). you should be benchmarking for those two scores.

Re: Is Intel within ARM’s reach? Pedestrian Detection shows the way

#30

Post by [deleted] »

mattst88 wrote: post #24
haricm wrote: post #11

Earlier quoted context omitted.

The model number used for the evaluation is Core™ i3-530

That's a Westmere from Jan 2010. Westmere -> Sandy Bridge -> Ivy Bridge -> Haswell. Comparing with something from 3.5 years and 3 generations ago is useful?

[deleted]
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