Slashdot is powered by your submissions, so send in your scoop


Forgot your password?
DEAL: For $25 - Add A Second Phone Number To Your Smartphone for life! Use promo code SLASHDOT25. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. Check out the new SourceForge HTML5 Internet speed test! ×

Comment Re:Nintendo.... (Score 1) 291

The PS2 has two vector coprocessors running at 300Mhz too, though only one of them is really useful for anything. Because of Sony's general philosophy of putting a bunch of weird specialty hardware in their machines, you can't just list CPU clock rates (as relevant as that ever is to anything).

The XBox is clearly more powerful than the PS2 (though not by as much as you suggest), but the GameCube isn't.

Where the XBox, the 360, and the Wii have the biggest advantage is that they're relatively easy to program for. Writing software for specialized vector processors is a pain.

Comment Re:What I want to see (Score 1) 228

Anonymous Coward:

RAID5 has terrible random write performance, because every write causes a write to every disk in the array.


I have to read from _every drive in the array_ in order to do a write, because the parity has to be calculated. Note that it's not the calculation that's slow, it's getting the data for it. So that's multiple operations to do a simple write.

No it does not. An x+1 parity computation only requires the parity block and the block being overwritten to write the new block. You take the parity, "subtract" the old data, and "add" the new data (in fact, the "subtract" and "add" are both just XOR).

Alternatively, if you're writing a full stripe, you can just compute the parity directly. This is of course preferable to doing reads, since reads are slow. Your random write performance is suffering because you have to read and write exactly two disks in the stripe.

I don't know why this old myth comes up so often. Any decent reference will explain how parity works. Maybe if Kari Byron explained RAID parity striping, it would sink in?

Doing random reads is not slow for an SSD, so of course the random write performance with RAID 5 will be much better with SSDs.

Comment Re:Your Goal: One Second or Less (Score 1) 654

Boot time for an OS is measured from boot loader to usable system, not from power button. This is a different measurement from boot time for a whole computer system.

Why the distinction?

Well, for example, Linux can't do anything if your BIOS sucks. It could boot in half a second, but it'll still take 90 seconds to get to the boot loader. What this means is that you use the OS time when comparing operating systems.

When comparing a Mac to an Dell computer, you compare the OS and the hardware boot time together, because Apple and Dell can actually fix that BIOS stuff if you complain enough.

So, the poster above was right to compare OSX to Ubuntu using the time from boot loader.

Comment Re:In the 1960s (Score 4, Insightful) 143

Broaden your vision. This is about making smaller components.

What can you do with smaller components? Well, right away, you can put more stuff in the case. Your iphonanopalmtop thing can have a foldout screen and keyboard, or a bigger battery, or it can simply be lighter. I don't know about you, but I find an iPhone a bit hefty.

Now, if you look beyond next week, smaller components let you do entirely new things. You think technology is sufficient now to put a computer in a palmtop? Whatever, dude.

I want a computer in my eyeglasses. Optically corrected screens overlaying my vision. High resolution. And I want them to weigh the same as a normal pair of glasses. Don't forget to throw in a video camera for good measure.

Can we build something like that now? Or course not. That sort of thing today is either a huge bulky piece of headgear, or it's moderately bulky and has a terrible display. We need better components: much smaller, much lower power, faster.

Don't ever say we've reached the limits of useful computer technology. Until you're plugged in directly via your visual cortex and have a robot butler who brings you waffles in the morning, we haven't even reached the limits of uses we can already imagine.


Submission + - Live Forever With Computers-If They Let Us

docinthemachine writes: "The inventor, author, and futurist Ray Kurzweil predicts that in 15 to 30 years, nanobots will roam our blood streams fixing diseased or aging organs, computers will back up our human memories, and conference calls will be replaced by meetings in virtual resorts. Information week reports on Kurzweil's lecture and conducts a fascinating interview. Kurzweil told a keynote audience at last week's SCO6 supercomputing conference his predictions of future life. Key points of his lecture: 1) people and computers will intermix with nanobots, blood cell-sized robots, that will be integrated into everything from our clothing to our bodies and brains. 2) Think of replacing everyone's "human body version 1.0 with nanotech that will repair or replace ailing or aging tissue, he says. Parts will become easily replaceable. 3) "A $1,000 worth of computation in the 2020s will be 1,000 times more powerful than the human brain," says Kurzweil, adding that in 25 years we'll have multiplied our computational power by a billion. 4) "Fifteen years from now, we'll have cured cancer and heart disease, or at least rendered them to manageable chronic conditions that aren't life threatening. Details and more information at : re/"

Slashdot Top Deals

Man is an animal that makes bargains: no other animal does this-- no dog exchanges bones with another. -- Adam Smith