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Comment: Re:Hmm, says here: (Score 5, Informative) 249

by marcansoft (#48306383) Attached to: New Atomic Clock Reaches the Boundaries of Timekeeping

Moving faster causes time to slow down (special relativity), but so does beeing in a deeper gravitational well (general relativity). As you move away from the Earth, both effects have opposite (but not equal) magnitude. I'm too lazy to do the math right now, but here's a walkthrough (for the case of GPS satellites, but the same equations hold; you just need to know the distance from Earth's center to Death Valley and to Mount Everest, and work out their linear velocity from that).

Comment: What is the point? (Score 4, Insightful) 88

by asa (#48247381) Attached to: Firefox OS Coming To Raspberry Pi

What was the point of Firefox? IE was free and was a proven and already well-established browser. By your logic, we never should have built Firefox and the Web should have stalled with IE6 in 2002.

The world needs a truly open mobile OS as much as it needed a truly open browser a decade ago. Android is open in name only and Google is hurriedly moving its most lucrative components into closed proprietary services and apps that aren't a part of open source Android. iOS is as closed as everything Apple does. Windows is getting some nice HTML5 support for apps, but not nearly enough. There's clearly an opportunity for HTML5 apps to compete on mobile if someone can build a solid alternative platform to the monopolies and silos we're all stuck with today.

Comment: Re:Once again proving ARM is awesome (Score 4, Insightful) 97

by marcansoft (#48160329) Attached to: Android On Intel x86 Tablet Performance Explored: Things Are Improving

Um, no, x86 CPUs are nothing like ARM and I'm not aware of any commercial x86 CPU with an ARM backend. Yes, modern x86 cores use a RISC-ish microcode backend with an x86 decoder frontend, but that doesn't say anything in favor of ARM. All it means is that the industry has collectively agreed that CISC as a microarchitecture is a stupid idea - not necessarily as an instruction set.

I'm not a fan of x86 myself, and I think it's a stupid design with a vast amount of baggage causing a significant power/performance impact when designing an x86 CPU (that Intel can get away with because they're a generation or two ahead of everyone else in silicon tech), but then again ARM isn't the pinnacle of RISC either (though I do think it's better than x86).

Me, I'll take whatever microarch gets the best performance per watt at whatever TDP is relevant. If Intel can pull that off with x86-64, by all means. If ARM AArch64 ends up ahead, awesome. If both are about equal, I'll take whatever's more practical based on other factors.

Comment: Re:Duh! (Score 1) 75

And since this is a camera passthrough, not an optical overlay, that's a glaring implementation flaw. Properly aligning the head tracking framerate, camera framerate, and rendering would let them render the virtual objects in lockstep with the physical ones (at least at speeds where motion blur isn't a significant issue; you can fake that by minimizing motion blur in the real image by using a short shutter time on the cameras).

Comment: Doesn't look unreasoanble (so far) (Score 3) 192

by marcansoft (#48009543) Attached to: NVIDIA Begins Requiring Signed GPU Firmware Images

So, they're locking out things that can brick the card (flash ROM/fuses, screw up thermal sensors) and apparently a hint of OS security (the Falcons that respond to userspace commands can no longer access physical memory, only virtual memory). The latter sounds somewhat bizarre, considering the firmware should be fully under the control of the driver, not userspace (I guess/hope?), but not unreasonable. Maybe there are software security reasons for this.

Nouveau is free to continue using its own free blobs or to switch to nvidia's. If they start adding restrictions that actively cripple useful features or are DRM nonsense, then I would start complaining, but so far it sounds like an attempt at protecting the hardware while maintaining manufacturing flexibility for nvidia. This isn't much different from devices which are fused at the factory with thermal parameters and with some units disabled; the only difference is that here firmware is involved.

NV seem to be turning friendlier towards nouveau, so I'd give them the benefit of the doubt. If they wanted to be evil, they would've just required signed firmware for the card to function at all. The fact that they're bothering to have non-secure modes and are only locking out very specific features suggests they're actively trying to play nicely with open source software.

Operating Systems

Outlining Thin Linux 221

Posted by Soulskill
from the tux-on-a-diet dept.
snydeq writes: Deep End's Paul Venezia follows up his call for splitting Linux distros in two by arguing that the new shape of the Linux server is thin, light, and fine-tuned to a single purpose. "Those of us who build and maintain large-scale Linux infrastructures would be happy to see a highly specific, highly stable mainstream distro that had no desktop package or dependency support whatsoever, so was not beholden to architectural changes made due to desktop package requirements. When you're rolling out a few hundred Linux VMs locally, in the cloud, or both, you won't manually log into them, much less need any type of graphical support. Frankly, you could lose the framebuffer too; it wouldn't matter unless you were running certain tests," Venezia writes. "It's only a matter of time before a Linux distribution that caters solely to these considerations becomes mainstream and is offered alongside more traditional distributions."

"Any excuse will serve a tyrant." -- Aesop