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Comment Re:Not the best summary... (Score 4, Insightful) 195

Most vaccines are not 100% effective. You need a certain percentage of the population to be immune for herd immunity to mean that they have little chance of contracting the disease (and, if they do, a good chance of being an isolated statistic rather than the centre of an outbreak). It only takes a few percent opting out of the vaccine to eliminate the herd immunity and make the entire population more vulnerable.

Comment Re:Wow, end of an era. (Score 1) 152

When people talk about an n-bit CPU, they're conflating a lot of things:
  • Register size (address and data register size on archs that have separate ones).
  • Largest ALU op size
  • Virtual address size
  • Physical address size
  • Bus data lane size
  • Bus address lane size

It's very rare to find a processor where all of these are the same. Intel tried marketing the Pentium as a 64-bit chip for a while because it had 64-bit ALU ops. Most '64-bit' processors actually have something like a 48-bit virtual and 40-bit physical address space, but 64-bit registers and ALU ops (and some have 128-bit and 256-bit vector registers and ALU ops). The Pentium Pro with PAE had a 36-bit physical but 32-bit virtual address space, so you only got 4GB of address space per process, but multiple processes could use more than 4GB between them. This is the opposite way around to what you want for an OS, where you want to be able to map all of physical memory into your kernel's virtual address space and is one of the reasons that PAE kernels came with a performance hit.

Comment Re:How soon until x86 is dropped? (Score 1) 152

Videogame programmer here. It wasn't really a compiler optimization issue. There's no compiler on the planet that can perform high-level optimizations like that.

Compiler engineer here. The vectorisation for the Cell wasn't the hard part, it was the data management. Autovectorisation and even autoparallelisation are done by some compilers (the Sun compiler suite was doing both before the Cell was introduced), and can be aided by OpenMP or similar annotations. If the Cell SPUs had been cache-coherent and had direct access to DRAM, then there's a good chance that a bit of investment in the compiler would have given a big speedup. The problem of deciding when to DMA data to and from the SPUs and where you need to add explicit synchronisation into the PPU was much, much harder. I've worked on a related problem in the context of automatic offload to GPUs and it turns out to be non-computable in most nontrivial cases (it depends heavily on accurate alias analysis).

Comment Re:How soon until x86 is dropped? (Score 1) 152

MIPS and PowerPC are still huge in embedded. MIPS is used on a huge number of cheap routers and a lot of these are in dire need of a better OS than they ship with (and many of them ship with a hacked-up Linux). PowerPC is mostly big in automotive, but IBM still sells machines and is willing to keep funding a lot of the software support. The same goes for S/390: a big part of IBM's sales pitch there is that you can spin up Linux VMs on it easily and run the OS that you're used to. SPARC these days basically means Oracle appliances. You don't buy a SPARC machine if you want to run Linux, you buy one if you want to do the vertical integration thing with Oracle (i.e. Oracle arranges you vertically with your head downwards and shakes until all of the money is integrated with their wallet).

Comment Re:ran debian on sparc for over 10 years (Score 1) 152

Someone needs to develop the software. The difference between open source and proprietary software is that open source software is developed by and for people who want to use it, proprietary software is developed by people who want to sell it. Successful projects are ones where the people who want to use it want to use it enough to fund development.

Comment Re:Sad Day (Score 1) 152

Debian hamm sucked quite a bit less than SunOS

We had a couple of those. You should have tried NetBSD. For a very long time, Linux had particularly bad handling of the SPARC TLB and NetBSD was faster to the extent that it was noticeable by the user in the GUI.

apart from the terrible quality of the CG3 driver in Xfree, which would lock the entire machine up solid after about 30 minutes of use

When was these? Even after they stopped being useful as stand-alone machines, we used them as dumb X servers and easily had a few weeks of XFree86 uptime.

Comment Re:Not the best summary... (Score 1) 195

Okay, let's remove the coercion then and have a proper libertarian solution. No one has to get vaccinated, but anyone who is not vaccinated is liable for and harm done by anyone that they infected with a disease, including joint liability for all outbreaks of that disease where the vaccinated number dropped below the number responsible for herd immunity.

By all means, go ahead and defend your right to kill people as a result of your negligence.

Comment Re:What's special here?? (Score 1) 107

No idea. Open source FPGA toolchains are definitely interesting, mostly because Altera and Xilinx compete on who can produce the worst software. Having a single toolchain that could target both (which this project is still a long way away from) would be very useful. Unfortunately, high-end FPGAs vary a lot both in the core logic block structure and the number and layout of the fixed-function macroblocks that are available.

Comment Re:The important details: Slower and over 540$ (Score 1) 75

The peak power consumption is important for one other reason: heat. The machine that I was talking about is in a small NAS case (4 drive bays, slimline optical drive, power distribution board, mini-ITX motherboard, no other spare space). It also on has a (fanless) 120W PSU, so it's quite easy to go over the available power if the CPU can spike up to a high peak. I'll keep the newer Intel chips in mind when I upgrade, but it looks as if most of the mini-ITX motherboards are still limited to 16GB of RAM and being able to upgrade to 32GB would be the main thing that would prompt me to replace the motherboard. Oh, and Haswell still doesn't have working FreeBSD drivers, so that wouldn't be an option yet.

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