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Mass Storage Leaves Microchips in the Dust
Roland Piquepaille writes "This article from Wired Magazine looks at storage with a new angle. 'Right now I am sitting in front of a whirring 60-gigabyte hard disk that cost less than $100. Do the math: If back then 10 megabytes cost $1,000, then 60 gigabytes would have cost x, where x = $6,000,000 and "back then" = 18 years ago. I'm sitting in front of $6,000,000 worth of mass storage, measured at mid-1980s prices. We have Moore's law for microprocessors. But who's coined a law for hard disks? In mass storage we have seen a 60,000-fold fall in price -- more than a dozen times the force of Moore's law.' DeLong also looks at a non-distant future when a $100 mass storage device will hold a full terabyte. He also thinks that with disk space becoming cheaper and cheaper, we'll be tempted to archive everything about ourselves, including pictures and videos. This is in fact the goal of the Gordon's Bell project, MyLifeBits. You can learn more about the MyLifeBits project by reading this NewsFactor Network article. Check this column for more details."
No only the price, the size of the drives. 18 years ago a 40 Mb HD has the size of a toaster...
The package said "Windows XP or better. Pentium Class Processor or better"... So I got a Mac with OS X
The one limited is network speed. Sure, if I've got enough room for a collection of 2 gigabyte raw avi movies, that's great. But if I can't get enough speed to download them quickly it will suck.
This has always bugged me... back in 1992, I had a 25MHz CPU, 8MB of RAM, a 660MB hard drive, 2.88MB floppies, and a 28.8 modem.
In 2003, I have a 2.2HGz CPU (88 times faster), 1024MB of RAM (128 times more), a 120GB hard drive (180 times more), 700MB CD-RWs (243 times bigger) yet only a 1Mbit (on a really good day!) network connection (about 35 times faster, no matter what the cable company claims.) And that's as fast as it has been for about 5 years now.
Where oh were is my 5Mbit cable modem? Heck, some poor bastards are still stuck using 56k modems...
It seems that network connections ony get faster in big bursts. In 1997, I had a 56k modem. In 1998, I had a 1Mbit DSL line. Maybe in 2008, I'll get fibre to my house.
"Tomorrow's forecast: a few sprinkles of genius with a chance of doom!" - Stewie Griffin
Drives today have 10.000 rpm or 15.000 rpm. Eight years ago the high end was 7200 rpm, 5400 before that...
;)
That's approximately a 2X performance increase per EIGHT YEARS. This is very very far from being impressive.
Disk seek time is dominated (today) by rotational latency. The fastest disks have seek times around 4ms, and that is pretty much the rotational latency on a 15000 rpm disk.
In order to improve disk performance (the seek time, not the throughput), disks need to spin faster. This does pose some interesting problems though...
A normal 3.5" drive has a platter with approximately 48mm radius, giving roughly 0.3 meter circumference. At 15000rpm the speed of the circumference is 75.4m/s.
Doing the math, this gives us a centripetal acceleration of v^2/r = 118435 m/s^2, or roughly 12085G. Sure as hell beats most drag racers out there (by more than a factor of 12000
The fun part is, that a simple doubling of the rotational speed, will do really interesting things to the acceleration (note the v^2 thing above).
A 30000rpm disk will have a centripetal acceleration of the circumference of approximately 48000G.
A mass-element at the circumference weighing one gram, will have a "pull" corresponding to (F=m*a) 118kg - which again will be approximately half a tonne on the 30000rpm disk.
You need to find a material that will weigh little, not deform under the given stress, and still have the necessary properties for use as a hard drive platter...