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The Past and Future of the Hard Drive
Snags writes "Brian Hayes of American Scientist has written a nice little historical review of hard drive technology, from the first hard drive (nice pic) made by IBM in 1956 to what may be available in 10-15 years. He muses on how to fill up a 120 TB hard drive with text, photos, audio, and video (60,000 hours of DVD's). Kind of ironic that this came in my mailbox today considering IBM's announcement."
Even Jesus hates listening to Creed.
Adding electronics to drives to gain more space is not a particular good idea in this day and age. You are not going to get 1000 bytes out of a 100 byte read very often, probably only if you are reading text. As you note Video and Graphics are usually stored in formats that are already compressed, so storing them on a drive with hardware compression wont win you much. And as the article says, text doesn't take up any noticable amount of space anyway. So even if you mostly care about your source code etc, you probably doesn't have anywhere near a GB, which is 1% of a modern drive.
Furthermore, compression and decompression takes time, so it would lower the performance of the drive somewhat (no idea how much, but some).
Wasn't Stacker those guys who made a piece of hardware to place between your drive and the IDE controller, to do the compression?
I cant remember who posted about it but it was on /. not long ago.
A professor in the US has designed a hard-drive with works just like RAM. Its blisteringly fast but is resistant. IE: after a reboot will not lose data.
Resistant Random Access Memory.
Apparently the limitations on size for these babies are phenomenal. were talking terabytes and terabytes.
however if this is going to be produced, or if its just vapourware is yet to be seen.
I would however revolutionarize our current data storage!
Whenever I see an announcement of the newest harddisc with record breaking capacity I think "How do you backup that beast?".
Whenever harddisc manufactureres manage to double the number of bits that can be written on an inch of a track they get an four fold increase of capacity. But unless you increase the rotational speed of the plattern the time to read the whole content of the harddisc will double as well since the recording/writing speed is proportional to the linear density.
And the rotational speed only increases very slowly - we recently saw the small jump from 5400 to 7200 RPM for the "standard" consumer (IDE) harddisc, the first for several years (I personally stick with 5400 for the cheapo IDE drives for the next few years. Reliability, you know --- see IBM)).
Given that the lower limit for the time to make a full backup of harddiscs will increase roughly with the square root of the growths of their sizes over the time.
The other problem is that backup devices and media affordable for the home user can't keep pace with the harrdiscs, so in my eyes the traditional full backup get's more and more inpractical.
One of the most cost effective backup devices for a harddisc today is another harddisc, but it still needs hours to mirror the content of one disc to another. RAID or something that keeps two discs in sync automagically in the background is no solution - it saves you from data loss by harddisc failures (good if you use IBM GXPs and the like) but it won't help you if you or your software have/has destroyed some important files you have created over the past few weeks/months.
Well, I don't know what other people do, but I stopped doing full backups of the whole disc: Thank God a large amount of files on my harddiscs is not backup worthy since in case of loss I won't miss it (think swap space or contents of a web cache), can easily recreate it (like mp3s made from my own CDs or object files - if you track netbsd-current you keep them around to save some time on future inkremental builds and don't delete them after "make install") or get it back from another of my machines, CDROM or the net.
So I only have to backup a fraction of my discs and the good news is that in absolute numbers the amount of data to backup doesn't grow nearly as fast as harddisc capacities. In my case with compression it easily fits on an older harddisc for complete backups and for weekly incremental backups I can still use and old 1GB DAT (DDS) tape I've got for free. It's not the best solution since recovering from desaster needs some time and a lot of manual work but I can sleep better than those who don't do backups at all...
1920 x 1080 pixels
16 bits/pixel x RGB = 6 bytes
60 frames/second
Yields 746,496,000 bytes/second. (Or about 8 parallel gigabit ethernet cards)
Do this at full bore, and you get 160,751 seconds of video, less than 2 days worth!
Sure, I know you could compress the video, but I've seen 1080p up close and personal, I noticed the artifacts in the video on the monitor of the broadcast quality HDTV demo, and the sales guy finally confessed that they just had to compress it to make it feasable to record it on tape.
If I noticed it right off the bat, someone will pay to have this quality level.
So... when do we get the petabyte storage?
--Mike--
I'm surprised no one else here has ripped a DVD to their HD before. 2 gig per hour seems like a minimum to me.
And even if it isn't, by the time the 120 TB disk come out, you think we're still going to be using the worst DVD format? 720p is supposed to be coming out in a few years. I can't find the page with the details now, but 720p will require a new type of DVD disk, one that can store up to 24 GB.
That's right, your DVD collection is going to become outdated and worthless as companies republish into the new "Hi-def" DVD format.
Let us say the average DVD uses 70% of the space, 16.8 GB. That's about 7,100 hours. Compression might be less effective on these disks, since the entire point of having Hi-Definition DVDs is the extra detail.
And I've come up with another use for a 120 TB drive. The biggest, most kick-ass TIVO in the world. Imagine having any TV show that was shown in your lifetime available to view.
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.