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ARM — Heretic In the Church of Intel, Moore's Law
ericatcw writes "For 30+ years, the PC industry has been as obsessed with under-the-hood performance: MIPs, MHz, transistors per chip. Blame Moore's Law, which effectively laid down the Gospel of marketing PCs like sports cars. But with mobile PCs and green computing coming to the fore, enter ARM, which is challenging the Gospel according to Moore with chips that are low-powered in both senses of the word. Some of its most popular CPUs have 100,000 transistors, fewer than a 12 MHz Intel 286 CPU from 1982 (download PDF). But they also consume as little as a quarter of a watt, which is why netbook makers are embracing them. It's 'megahertz per milli-watt,' that counts, according to ARM exec Ian Drew, who predicts that 6-10 ARM-based netbooks running Linux and costing just around $200 should arrive this year starting in July."
Not really. ARM has been around for a long time. Its biggest use is in embedded systems- phones, printers, etc. In those markets cost and power usage matter more than performance. They may make a line with more performance eventually, but they make money hands over fist in places where pennies matter (after all, if you sell 1M phones with a processor thats 5cents cheaper, thats 50K more profit). They won't give that up.
I still have more fans than freaks. WTF is wrong with you people?
You're right. Both approaches have their place. What you're observing is the manifestation of an overriding need to prove one's superior intellect. It's a sign of poor socialization.
I, for one, welcome multiple approaches to achieving multiple goals.
512 MB RAM, 20 GB disk, 200 GB transfer, five datacenters. $19.95/month.
What happens when those 6-10 netbooks get sold? What about the rest of us? Seems like it's hardly worth it to build so few. They should be building them by the thousands!
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
They are the only chips that you can program and keep your sanity.
The ARM code is just beautyful design, one weeps with joy after struggling through x86 hell.
And computing/electric power ratio is fantastic.
Web browsers are interpreters, which are going to be slower than machines that run pre-compiled code
It's worse than that: In addition to HTML, a web browser must parse/interpret JavaScript, Java, CSS, XHTML, Flash (if Adobe ever gets onboard), and regular XML just to display the modern, JavaScript-heavy web application. This gets resource intensive if, say, using an app such as Google Docs on a netbook with little memory, since the browser keeps the DOM structure in memory, and it gets exponential if the user has multiple tabs open with an app/page in each.
/. a while back, but how well they would maintain this for both x86 AND ARM remains another story, in addition to all of the other problems that could ensue, especially at the security level (a bug in the JS parser leading to direct remote code execution, etc.).
A server pre-parsing HTML would mean a browser/server handshake, something IE and IIS could easily do moreso than Apache(2)/Lighttpd and Firefox/Safari/Chrome. Opera does this with their mobile platform, but it is still far from perfecting JavaScript precompilation or even delegating this to the lower-resource device at the client end.
Google was contemplating compiling JavaScript to pure native code in a story I read here on
It's problems like these that keep 300Mhz netbooks with little RAM from being very efficient with full-scale web apps. Just my firefox I'm running now, I have about 20 tabs (mostly regular HTML) open and it runs up my dual-core CPU so high that my fan is running (not much in the background), and it eats memory like crazy. But as far as MS breaking the Wintel relationship to pursue ARM-based netbooks, I don't see it happening unless something drastic happens.
I think the ARM netbooks are going to have a monster market, like eventually over 100 million a year.
That may sound crazy, but you have to look at the demographics. There are about 6 1/2 billion people in the world. About 1 1/2 billion are in the developed world or the richer parts of the developed world. They all have computers. At the other end are about a billion who are are desperately poor.
That leaves around 3 billion who are in-between. These are the people who have enough money to buy things like bicycles, motor bikes, televisions, and cell phones. A great many would love to own a computer, and indeed many of them spend a lot of time at cybercafes. But they can't afford the price. And there is another problem, namely that half of these people live in areas with no electricity, and for most of the rest the electric service is very eratic.
The first generation of netbooks was too expensive for this gigantic potential market, and besides they used too much electricity. But the new ARM netbooks will be enough cheaper for perhaps 500 million more people, and they will use far less electricity, too. Furthermore prices are just going to keep going down. Pixel Qi is planing on designing $75 models in a few years. Every time prices drop another huge group will join the market.
This all is a huge problem for Microsoft. On the one hand, it would hate to charge the very low license fees it would need to get anywhere in this new market, on the other hand it can hardly afford to ignore it.
You do realize that the Cortex series of ARM cores can get to around 1GHz, and that the Marvell (formerly Intel) XScale chips can scale to 1.25GHz easily. And that's when they're drawing a quarter to a half a watt. At worse, you're getting 1GHz/watt.
ARM is used everywhere, it scales handily from fleapower devices, to the GHz range used in the latest smartphones. For every x86 CPU sold, the PC containing it probably contains several ARM processors (Bluetooth and WiFi being extremely common peripherals with ARM processors). A cellphone usually has 2 - one driving the UI, and one in the radio, and maybe two more (again, Bluetooth and WiFi).
400-667MHz seems to be the "sweet spot" right now for a cellphone's ARM processor... (iPhone has it at 400-416MHz, the Palm Pre has a Cortex A8 at 667MHz). And the whole cellphone power management has to be able to drop power consumption to a mere 3 milliamps or so, including the power spikes to maintain a link to the cell towers.
Atom tries, but it's still an order of magnitude too much power for an entire system...
ARM has a couple processors already that are pretty high on the performance measurement. For instance the Arm Cortex A9 has a dual issue pipeline, and limited support for out of order processing (similar to the original Pentium processor in that regard). This chip also can contain up to 4 cores, and have up to a 2MB L2 cache. I think they can run up to about 1GHz. They also have full support for floating point and all that good stuff. I'm pretty sure ARM is also working on developing an true OoO processor that will likely be running in the GHz range which would likely be ideal for a netbook.
Remember, with a netbook, you don't gain much by lowering the CPUs power consumption to less than 5 watts or so. The reason for this is simple, the display, ram, hard drives and everything else consume enough power that it won't really help battery life very much. I can imagine though that a quad core ARM A9 at 1GHz would make for a really nice netbook. Having multiple cores is nice on those for web browsing (playing flash in the background of your tabs, etc), and also for many media tasks. It would also be great if they included a graphics chip (or gpu as part of a SoC system) that could handle h.264 decoding for the netbook.
Phil
Aw, how innocent you are.
Religion, politics, benchmarks, the check is in the mail, I won't cum in your mouth.
Netbooks can use much less power than they do today. Real netbooks use solid state storage, which has negligible idle power consumption and very low read power consumption. In the future, RAM may be replaced by one of the contenders for persistent RAM (e.g. MRAM) with zero idle power consumption. Backlit TFT displays will at some point be replaced by E-Paper which only uses power to change the display. At that point, the CPU and the wireless network are about the only consumers of power, so every improvement counts.