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Mobile Phones vs. Supercomputers of the Past
An anonymous reader writes "The recently published Top 500 list of the world's fastest supercomputers is based on the Linpack benchmark developed decades ago by Jack Dongarra. This same test has been ported to Android mobile phones, which means that we can compare the performance of our phones against that of the supercomputers of the past. For example, a tweaked Motorola Droid can hit 52 Mflop/s, which is more than 15 times faster than the CPUs used in the 1979 Cray-1." But even today's most powerful cellphones don't come with an integrated bench.
"On the other hand, I wonder how much amazing stuff I would see had I been born even just 20 years later (than 1984)"
If you were born in 2004 you would have missed out on everything. All you'd know is multi-core processors, terabytes and petabytes, touchscreen everything, wireless internet everywhere, 24/7 access to everyone you don't really know and directions to anywhere from anywhere available in your pocket. You'd have no appreciation for any of it and probably know nothing about computers because modern operating systems are far better than offerings in the 90s.
Trust me when I say you were born at the right time.
my karma will be here long after I'm gone
Ah but all work on the Cray-1 was programed to be as parallel as possible, so cpu to cpu isn't an appropriate comparison. Much more useful is device output, in which case the 136 MFLOPS is significantly better performance than the 52 MFLOPS.
That is of course not considering that the designers of the Java applet that runs the benchmark admit that you're moreso benchmarking the java effeciency of a given device with their app than the full performance of the device.
Well, also not considering the $6m to $8m price tag of the Cray-1 vs the $200 (after rebate and 2 year plan) price tag of the Droid. Even factoring in inflation, I think my droid wins the performance-per-dollar crown by a little bit.
It does mean though that the intial statement "15 times faster than the cpus in the cray-1" is not quite reality. more like 5 times faster.
Not rendering bitty little colour screens or scanning for viruses. Plus the code was written to extract every last drop of power out of the architecture. So when you compare the amount of WORK a machine from the 70s or 80s did (my university's mainframe had a FORTRAN complier that needed less that 131kWord of memory - today the GRUB bootloader is bigger than that) with a more modern box, with all its overheads and inefficiencies, the balance isn't as great as the scoffers might think.
Does that make it any less impressive that a cell phone is putting up these kinds of numbers? Does it make it less impressive that you can code up an Linpack in Java, throw it at a JVM and rely on JIT compiler to optimize the DAXPY for the hardware on the fly? I think it both of those things are pretty damn impressive.
Today, the games you can play on your iPhone/Android or even the aging Nintendo DS have better graphics!! Resolution is a lot lower (not 3000x5000!) but at the screen size it certainly looks much better - and rendered in real time!
Actually, for mobile devices, the most important metric is performance per unit of power instead of just performance per unit time. After a certain speed/throughput has been reached, nobody cares how fast the CPU is, only how long the battery lasts.
For scientific purposes, back when Cray was building systems, you got charged by the second you had access to the computer. So you carefully composed the solution to your problem to make darned sure every whizz-bang aspect of the computer was doing something useful all the time. Today, you just want to play a game for a while, then make a voice call, and don't want the battery to fizzle out before you get home (and maybe have some juice left for watching a show during your train ride home.)
Mobile devices don't try to match the throughput of all parts of the system, because it's not in anybody's interest to keep the I/O subsystem saturated close to capacity 100% of the time you're using your Droid/iPhone... in fact, they turn them off (go into a low power state) and do aggressive power management that is coordinated system-wide.