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Ultra Fast Disk Drives With No Moving Parts
saccade.com writes "Let's face it, the slowest part
of PC's today is the disk drive. Bit
Micro has come up with a nifty solution - flash memory based
disk drives available in typical
disk
form-factors. These e-disks are electrically compatible
with ATA, SCSI, etc. but run orders of magnitude faster - access
times down to 40 usec and transfer rates over 100 MB/sec. What's
the catch? Cost. Currently going for just under $1K/G, a 30G model
I recently held in my hand was worth much more than my car. However,
as flash memory prices drop, so do the price of these drives.
Within the decade the spinning hard disk may go the way
of the floppy and CRT."
I wonder how long you can beat at a device like this in a server environment before it croaks. I'd give it no more than a year life expectancy, but hey, I'm feeling pessimistic.
I am feeling fat and sassy
I need an EE to build an ata interface to a raid series of about 100 flash either (SD or compact). Now allow the end user to plug in how many cards he wishes and just use them. Imaging that if you have a raid 5 setup of say 128 256mb cards costing about $40 each would cost about $5000 1/6th of the $30k and it is end user upgraded and so cool to be able to ad more storage instead of rebuilding a whole computer and drive.
Maybe not, but if they start going a little bit mainstream, we'll start to see the cost go down. I know I've thought about using some sort of flash device for my boot drive just to have extremely fast boots.
100,000 writes isn't gonna last long in todays bandwidth intensive video/mp3 world
no moving parts and non-magnetic media is a worthy goal but until we can cure terrible storage lifetimes they wont be much use if i have to worry about the mess backups of backups, as we know from sci-fi all it takes is a big EM burst from the sun and everything you and i have done is gone !
future generations will look back at us and say "they used to store it on WHAT !?"
I've always found the best way to deal with the problem of slow disks is to max out the memory in the PC and use a hefty chunk of it as a RAM disk. When done or needing to backup, tarball the whole disk, write it once to the hard drive.
:)
Of course, this assumes you're working on a stable OS with decent tools and good memory management. If you're not, you can be.
Everything in the Universe sucks: It's the law!
I know that 10000 writes seems like a lot, and perhaps it is. Anyone knows how this figure looks for normal harddrives?
Still it seems to me that the limited number of writes sets the biggest limitation.
...printer.
Technically, a printer is a peripheral, not a part. Whatever. All printers are evil: Too slow, too big, too expensive, too quirky. Ackk.
-- Slashdot: When Public Access TV Says "No"
Old enough, so the first 'generation' of SSD companies is already out of business. E.g. Platypus (I think that was the name) build RAM based solid state drives, some of them in the right shape and with appropriate disk interfaces to match existing disk drives.
I looked into SSD for a database at one point. But I found that you can get almost the same performance by using lots of drives in a fast RAID setup. Striping the content over multiple disks does wonders! And its much cheaper.
E.g. look at something like a 12 disk setup with RAID 5+1. You got a full mirror, and essentialy 4-8 times the speed of a single drive. So you are already close to the 'order of magnitude' they SSD drives claim.
---- join dshield.org Distributed Intrusion Detec
Not always. Sometimes things are expensive because they are technically difficult to manufacture, or because the raw materials are expensive, or because the environmental regulations are expensive.
memory chips require many expensive and hazardous chemicals to manufacture like fuming sulfuric acid for dissolving the photoresist inks and hydroflouric acid for etching the circuits. These chemicals have a large environmental regulation cost associated with them that's not going to go down any time in the forseeable future and is entirely outside the control of any manufacturing process.
You can tell a great deal about the character of a man by observing those who hate him.
"...and is entirely outside the control of any manufacturing process."
ANY process? I think that was the point - if someone can come up with a new process, we could reduce costs. The more these are used, the more incentive there is to research new processes.
As far as I can recall, there ARE people working on alternatives to memory as we know it.
The same thing happened with LCDs, as pointed out - CRTs have a bottom line cost - the cost of the components have a bottom line that means that LCDs should, at some point, be cheaper - the processes are still be refined and improved, and there's not a whole lot of leeway anymore with CRTs.
Stupid sexy Flanders.
Without giving away too much (and getting fired in the process) there is a whole new tech on the horizon. It still uses all the nasty chemicles, but in traditional flash memory, the chip is broken into three major components:
charge punps (to provide the 9.5-12 volts required to program the chip from the punny 1.8 - 3.3 volt supply
the control circuitry (basically a mini CPU)
the flash array
all these elements are "flat", that is they are one structure deep. This new tech coming up, if someone can perfect it, uses multiple layers to make the flash array several layers deep. Thus you could (in theory) shrink your die size while increasing the memory density.
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
all these elements are "flat", that is they are one structure deep. This new tech coming up, if someone can perfect it, uses multiple layers to make the flash array several layers deep. Thus you could (in theory) shrink your die size while increasing the memory density.
This turns out not to help much. Multi-layer chips add mask steps roughly in proportion to the number of layers. While you save on the cost of wafer area, your processing steps cost a lot of money too, so you rapidly reach a point of diminishing returns. Building multi-layer devices also requires making transistors on epitaxial silicon layers, which generally have far worse performance properties than the monocrystalline wafer (even SOI processes generally work by building devices on a silicon wafer, and either flipping the chip and back-etching or using a buried oxide layer, as opposed to depositing a silicon film).
3D chips have been a holy grail for density reasons for decades, but they turn out to be expensive to manufacture and poorly-performing for the reasons noted above, and for microprocessors, at least, they're now a pretty much obsolete solution, as heat generation is what limits chip performance (and a multi-layer chip gives you that much more heat generation per unit area).
If your company can pull it off in a useful way for storage, they'll deserve kudos, of course.