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Samsung Announces Flash-Based Disk Drive
doc6502 writes "Samsung has announced flash-based disk drives with a 16 GB capacity, with an aim to get the drives to market by the end of the year. The (short) article suggests that this could be a big boost to laptop owners, as battery life could be seriously extended if there isn't a big high-speed motor to power constantly. The drives should be fast, too."
Memtech has been doing this sort of thing for a while now.
Still, this is great news...the more companies that switch to flash technology, the more the technology itself will become mainstream. It's about time we did away with platter-based HDDs.
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it's non-volatile flash memory.
Here's a great paper about flash technology in HDD applications. The document is a bit lengthy, but the conclusion is that today's flash technology allows for enough erase/write cycles to make them more than viable for HDD use.
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Depending on the chip and manufacturer, you can get Flash that can be written up to a million times.
What this means for you is that the manufacturers will get the cheap stuff. That means you'll get 100k writes if you're lucky, and most likely you'll get stuck with 10k.
Since that will probably take you past the 1 year warranty, the drive manufacturers will say, "Ha, ha. Thank you for your money. Please buy another drive."
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
Yes, the life of the flash is a factor here, but you're missing a couple of points.
First, the life of modern parts if much higher than you stated. I think it's in the hundreds of thousands if not millions of writes.
Second, they can apply the same techniques as spinning drives to remap bad blocks so that when a block stops working, it gets replaced by a spare one that was never seen by the user. A similar remapping can be done to swap heavily-used and lightly-used blocks to even out the wear and extend the life.
check m-systems http://www.m-sys.com/ they have a 176G flash scsi disk there, also a 'low cost' 8G ide flash drive in 1.8 and 2.5" so how is this news exactly ?
Again, please refer to this paper about flash technology in HDD applications. The document is a bit lengthy, but the conclusion is that today's flash technology allows for enough erase/write cycles to make them more than viable for HDD use.
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Don't know about MTBF, but as they're not mechanical I'm sure they can live much longer than spinning disks (except for the write issue, but that can be buffered with more spares). As for defragging - don't think so, as defragging is only useful to reduce seek times while accessing the same file (the same file isn't physically scattered on disk). As there are no seek times here, why bother defragging.. file systems could be a bit simpler too.
> Wake me up when they're introduced.
From TFA:
"Flash-based drives based on the new technology are expected on the market by August of this year."
A couple of months and they will be.
Yes. Flash memory can only be written to a finite number of times, and your flash disk-drive will stop working at some point.
Exactly like platter-based disk drives.
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The CF+ and Compact Flash specification 3.0 includes UDMA 33 and UDMA 66 support. I've seen references to certain cards and CF->IDE adapters that support DMA, so that problem is partially solved, and will get better.
As for the problem of sustained speeds, there's always RAID 0...
steve
Oh, you're not stuck, you're just unable to let go of the onion rings.
LOC is usually measured as 20 Terabytes (although estimates range from 17-20, 20 is almost always taken). 20 TB = 20,480 GB so 16GB would be .08% of one LOC (78/100,000).
Regards,
Steve
As someone else mentioned, all hard drives eventually fail. Even SCSI drives. It's a mechanical device and all mechanical devices eventually fail. You realize that the slowest device in your system is the hard drive, right? You realize that your hard drive and your optical drive are the only moving parts in your computer and thus, are more prone to failure? If you want to keep using a mechanical device in this day and age, be my guest. But to me, this seems to be a step towards solid state drives for the masses and I applaud the move.
Something Witty Goes Here
The Inq has a picture of the flash drive at http://www.theinquirer.net/?article=23425.
Flash has to be erased (slow operation) before being written (fast). This is typically accomplished by having the OS-driver / firmware perform the erase operations for unused sectors in the background. Thus there's _always_ a set of pre-erased sectors ready-to-go.
Once erased, the available sectors are put in a free list. When the OS commands a sector to be written, the next available one is selected from the free list, and assigned to the sector number the OS requested. Thus there is a round-robin approach to using sectors. While one block of flash may be written up to 100,000 times, this round-robin approach makes it so that 100,000 is roughly multiplied by the number of free sectors in the rotating list. Thus, you effectively have an unlimited number of writes on flash.
When a sector can no longer be erased, it is dropped from the available list. Over a long period of time, your flash will be eaten up with dead sectors. You might not want to run a Transaction Processing Database System on this kind of media, but for a laptop computer, its perfect.
There's no time to stop for gas, we're already late.
I'm sure most of the battery life goes to spinning the platter
I'm not so sure. Most of these have a few MBs of RAM, so the platters just spin once in a little while to fill-up the 10 min buffer.
jim frost
jimf@frostbytes.com
If the OS still hits the drive then you're not going to get the most out of hybrid drives. There was an interesting presentation at Microsoft WinHEC last month. The presenter said that Samsung's new flash was significantly faster so it eliminated a lot of the flash performance penalty. You can see the slides here:
t oc10
http://www.microsoft.com/whdc/winhec/Pres05.mspx#
"Hybrid Hard Drives with Non-Volatile Flash and Longhorn [WinHEC 2005; 207 KB]"
The presentation slants towards Longhorn but you can see where the technology is going.