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IBM Prepares 100-Terabyte Tape Drives
Roland Piquepaille writes "It's a well-known fact that we're living in an era of data explosion, and that it's not about to stop. So it's not really surprising that IBM researchers are eyeing 100T-byte tape drive. Yes, you read correctly. They want to increase the capacity storage of their largest units by 250 times, from 400 GB to 100 TB. In order to achieve this goal, they're borrowing "nanopatterning" techniques derived from the microprocessor division. Today, the size of a tape track is about 10 microns. They want to reduce it to 0.5 micron -- or 500 nanometers -- in about five years. IBM doesn't really say when a 100-Terabyte tape drive will be available. But more importantly, the company doesn't say a word about future data transfer rates, which today reach a 80 MB/s. Read this overview for more comments about this problem of data transfer rates."
Heck, even if you were to connect a drive like that to the firewire-800 port (800mbps) port on a new (today) PowerMac G5, it'd take over 277 HOURS to fill that tape! (assuming complete bus saturation and an 8-bit-byte)
What is the difference between a small revolutionary change and a large evolutionary change?
Roland Piquepaille and Slashdot: Is there a connection?
I think most of you are aware of the controversy surrounding regular Slashdot article submitter Roland Piquepaille. For those of you who don't know, please allow me to bring forth all the facts. Roland Piquepaille has an online journal (I refuse to use the word "blog") located at www.primidi.com. It is titled "Roland Piquepaille's Technology Trends". It consists almost entirely of content, both text and pictures, taken from reputable news websites and online technical journals. He does give credit to the other websites, but it wasn't always so. Only after many complaints were raised by the Slashdot readership did he start giving credit where credit was due. However, this is not what the controversy is about.
Roland Piquepaille's Technology Trends serves online advertisements through a service called Blogads, located at www.blogads.com. Blogads is not your traditional online advertiser; rather than base payments on click-throughs, Blogads pays a flat fee based on the level of traffic your online journal generates. This way Blogads can guarantee that an advertisement on a particular online journal will reach a particular number of users. So advertisements on high traffic online journals are appropriately more expensive to buy, but the advertisement is guaranteed to be seen by a large amount of people. This, in turn, encourages people like Roland Piquepaille to try their best to increase traffic to their journals in order to increase the going rates for advertisements on their web pages. But advertisers do have some flexibility. Blogads serves two classes of advertisements. The premium ad space that is seen at the top of the web page by all viewers is reserved for "Special Advertisers"; it holds only one advertisement. The secondary ad space is located near the bottom half of the page, so that the user must scroll down the window to see it. This space can contain up to four advertisements and is reserved for regular advertisers, or just "Advertisers". Visit Roland Piquepaille's Technology Trends (www.primidi.com) to see it for yourself.
Before we talk about money, let's talk about the service that Roland Piquepaille provides in his journal. He goes out and looks for interesting articles about new and emerging technologies. He provides a very brief overview of the articles, then copies a few choice paragraphs and the occasional picture from each article and puts them up on his web page. Finally, he adds a minimal amount of original content between the copied-and-pasted text in an effort to make the journal entry coherent and appear to add value to the original articles. Nothing more, nothing less.
Now let's talk about money. Visit http://www.blogads.com/order_html?adstrip_category =tech&politics= to check the following facts for yourself. As of today, December XX 2004, the going rate for the premium advertisement space on Roland Piquepaille's Technology Trends is $375 for one month. One of the four standard advertisements costs $150 for one month. So, the maximum advertising space brings in $375 x 1 + $150 x 4 = $975 for one month. Obviously not all $975 will go directly to Roland Piquepaille, as Blogads gets a portion of that as a service fee, but he will receive the majority of it. According to the FAQ, Blogads takes 20%. So Roland Piquepaille gets 80% of $975, a maximum of $780 each month. www.primidi.com is hosted by clara.net (look it up at http://www.networksolutions.com/en_US/whois/index. jhtml [networksolutions.com]). Browsing clara.net's hosting solutions, the most expensive hosting service is their Clarahost Advanced (http://
The IBM enterprise SAN device -- shark -- is only able to crank data out at about 35MB/s per disk pack, assuming sole access. When you've got multiple systems hitting one disk pack it drops dramatically from that.
So 80MB/s is more than their disk systems can do anyway, unless you're pulling data from multiple packs.
"But actually trying to use m4 as a general-purpose langage would be deeply perverse" --ESR
Yeah ... and I've found that it's really, really hard to get them to understand why it isn't. "But it's making a copy of everything I save!"
I try to point out that "Yes, it is! INCLUDING that trojan you just installed and all the files it just are erased are now gone from BOTH drives!" Argghh.
But usually it is after they themselves nuke something important and want to know how to restore it from their "backup" do they finally understand. So far as I'm concerned, a backup isn't a backup until you remove it from the computer and store it somewhere safe off-site.
The higher the technology, the sharper that two-edged sword.
The simple answer is that the data is not stored and to end - - - - - in a linear array. The data is stored in a 2 dimensional grid, using both the width of the tape as well as the linear position on the reel to store data. In many cases, the data is stored in a biased array of rows /////
Thus the data density depends on not just the size of the individual particles storing the bits, but also on the possible arrangement of the grid, be it rectangular, biased arrays, hexoganal, etc.
Additionally, most backup systems include redundancy in the written patterns, to protect against degradation due to environmentla exposure. The most common I am familiar with is the storage of a reversible cyclic redundancy check (CRC) in the written blocks. The block size varies from program to program, as does the compression algorithm chosen.
So if we assume a rectangular array of bits, with mild bias, we get a grid #. If each bit on the grid is halved in size, the data density, barring other changes, is quadrupled. Changes to the pattern made possible may increase this further, as well as advances in the heads.
Current heads can only read at a certain speed, so a trade off is made between spool speed and data density, meaning that not 100% of the space on the tape is lines of data, there is alos white space, unused on the tape. If a better head can read a more densly packed datastream, then you could very well make a 250x increase in total capacity.
It's been a long time since I worked with tape drive technology, so this is just an approximate explanation, of course.
You can have it fast, accurate, or pretty. Pick any 2.
AC, whoever you are, you've done outstanding research, and I salute you.
I'd make you a Friend, if I knew your ID.
-kgj
-kgj
the capacity of your brain. your brain has about 100Gig of neurons. each with about 1000 connections to other neurons each associated with a "weight" that store the information. so if we assume 16bit weight.. we have a raw 200TByte of information storage in your brain...a lot of this is propablay wasted for basic live functioning....