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From the Wikipedia article: > Broadcom BCM2836 (quad-core A7 + VideoCore IV GPU), designed specifically for Raspberry Pi 2[7] No, it says BCM2836 was designed

by vardump 11y ago

From the Wikipedia article: > Broadcom BCM2836 (quad-core A7 + VideoCore IV GPU), designed specifically for Raspberry Pi 2[7] No, it says BCM2836 was designed specifically for Raspberry Pi 2. Cortex A7 is a pretty old design, probably that way RPi 2 costs could be kept low. Edit: Here's Anandtech 2011 article about Cortex A7: http://www.anandtech.com/show/4991/arms-cortex-a7-bringing-cheaper-dualcore-more-power-efficient-highend-devices http://www.anandtech.com/show/4991/arms-cortex-a7-bringing-c... Wikipedia's Cortex series DMIPS/MHz table. It says Cortex A7 (1.9 DMIPS/MHz) is roughly as fast per clock as Cortex A8 (2.0 DMIPS/MHz) released in 2003: https://en.wikipedia.org/wiki/Comparison_of_ARMv7-A_cores https://en.wikipedia.org/wiki/Comparison_of_ARMv7-A_cores

claudius 11y ago
Interesting. So how would a reasonably new ARM core compare to this? The point is, the Xeon is definitely outdated and the Cortex A7 seems to be a little bit dusty as well, so…what exactly was the point of this comparison? Two CPUs from two different (or equal, if you take 2010/2011) points in time are roughly comparable?
- darklajid 11y ago
  I feel the point of the comparison was answering the question "Might it be feasible to replace our current infrastructure¹ with an arm based solution², and at the same time: Can we benefit from more cores, lower clock speeds" 1: The article uses their current dev system - there's no reason to buy a shiny new setup if that dev system works fine today and is 'fast enough' 2: The article explicitly mentions upcoming arm8 server boards but uses RPi2s as a general (and low) approximation for 'cheap arm performance' and to test their setup in a multi-node environment (vs. 'one single vm') I think the article explains quite well what it wanted to do and doesn't claim 'arm is better' or anything like that. For their workload, using Erlang/OTP and their real world application, a multi-node arm-based architecture might be feasible.
  - vidarh 11y ago
    But then pointing out the cost of their current system is confusing matters - as I've pointed out in another comment, a similar performance system today can easily be had for 1/5th of the price they list. They're comparing against a system that is old, slow and expensive.

by vardump 11y ago

claudius 11y ago

Interesting. So how would a reasonably new ARM core compare to this? The point is, the Xeon is definitely outdated and the Cortex A7 seems to be a little bit dusty as well, so…what exactly was the point of this comparison? Two CPUs from two different (or equal, if you take 2010/2011) points in time are roughly comparable?

darklajid 11y ago
I feel the point of the comparison was answering the question "Might it be feasible to replace our current infrastructure¹ with an arm based solution², and at the same time: Can we benefit from more cores, lower clock speeds" 1: The article uses their current dev system - there's no reason to buy a shiny new setup if that dev system works fine today and is 'fast enough' 2: The article explicitly mentions upcoming arm8 server boards but uses RPi2s as a general (and low) approximation for 'cheap arm performance' and to test their setup in a multi-node environment (vs. 'one single vm') I think the article explains quite well what it wanted to do and doesn't claim 'arm is better' or anything like that. For their workload, using Erlang/OTP and their real world application, a multi-node arm-based architecture might be feasible.
- vidarh 11y ago
  But then pointing out the cost of their current system is confusing matters - as I've pointed out in another comment, a similar performance system today can easily be had for 1/5th of the price they list. They're comparing against a system that is old, slow and expensive.