The fundamental problem with NAND-based solid-state drives is that they use NAND flash memory--the same stuff that you find in USB flash drives, media cards, etc.
The advantages of NAND is that NAND is both ubiquitous and cheap. There are scads of vendors who already make flash-memory products, and all they need to do to make SSDs are to slap together a PCB with some NAND chips, a SATA 3Gb/s interface, a controller (usually incorporating some sort of wear-leveling algorithm) and a bit of cache.
The disadvantages of NAND include limited read/write cycles (typically ~10K for multi-level cell drives) and the fact that writing new data to a block involves copying the whole block to cache, erasing it, modifying it in cache, and rewriting it.
This isn't a problem if you're writing to blank sectors. But if you're writing, say, 4KB of data to a 512KB block that previously contained part of a larger file, you have to copy the whole 512KB block to cache, edit it to include the 4KB of data, erase the block, and rewrite it from cache. Multiply this by a large sequence of random writes, and of course you'll see some slowdown.
SSDs will always have this problem to some degree as long as they use the same NAND flash architecture as any other flash media. For SSDs to really effectively compete with magnetic media they need to start from scratch.
Of course, then we wouldn't have the SSD explosion we see today, which is made possible by the low cost and high availability of NAND flash chips.
Agreed. Hell, I won't consider an SSD until I can get one that competes with a WD Velociraptor in write speeds and $/GB. That'll happen considerably sooner than an SSD that can compete with the 1.5TB 'Cuda for price / capacity, but it will still be years down the road.
No need to thank me, citizen, just doing my part to spead Literacy, Justice, and the American Way! Literacy and Justice are part of the American Way again?
Placebo is the term for the sugar pill given to patients undergoing clinical trial. It is a specific form of fake drug. What these criminals are peddling is not just plain fake drug, not something guaranteed to cause no harm. So this should not be called a placebo. Even the *placebos* are fake? Is nothing sacred?!
It'll be interesting to see how many third parties will release generic products free, (a la a lot of the 3.5Ed d20 stuff available online) or whether we sweaty basement-dwellers will merely have more choices as to which among several publishers we send our disposable income to.
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The fundamental problem with NAND-based solid-state drives is that they use NAND flash memory--the same stuff that you find in USB flash drives, media cards, etc.
The advantages of NAND is that NAND is both ubiquitous and cheap. There are scads of vendors who already make flash-memory products, and all they need to do to make SSDs are to slap together a PCB with some NAND chips, a SATA 3Gb/s interface, a controller (usually incorporating some sort of wear-leveling algorithm) and a bit of cache.
The disadvantages of NAND include limited read/write cycles (typically ~10K for multi-level cell drives) and the fact that writing new data to a block involves copying the whole block to cache, erasing it, modifying it in cache, and rewriting it.
This isn't a problem if you're writing to blank sectors. But if you're writing, say, 4KB of data to a 512KB block that previously contained part of a larger file, you have to copy the whole 512KB block to cache, edit it to include the 4KB of data, erase the block, and rewrite it from cache. Multiply this by a large sequence of random writes, and of course you'll see some slowdown.
SSDs will always have this problem to some degree as long as they use the same NAND flash architecture as any other flash media. For SSDs to really effectively compete with magnetic media they need to start from scratch.
Of course, then we wouldn't have the SSD explosion we see today, which is made possible by the low cost and high availability of NAND flash chips.
Agreed. Hell, I won't consider an SSD until I can get one that competes with a WD Velociraptor in write speeds and $/GB. That'll happen considerably sooner than an SSD that can compete with the 1.5TB 'Cuda for price / capacity, but it will still be years down the road.
I take it you've never read Otherland.
Does anyone else find it as depressing as I do that such obviously intelligent, motivated machines can't find a more productive use of their talents?
FTFY
It'll be interesting to see how many third parties will release generic products free, (a la a lot of the 3.5Ed d20 stuff available online) or whether we sweaty basement-dwellers will merely have more choices as to which among several publishers we send our disposable income to.
Surely you're not suggesting there are girls among us.
This system would be great for locating lost objects. I for one have misplaced my Sarah Connor.
Gallagher sighs in relief.
I broke a game boy on my forehead Christmas Day of 1994.
Well. I broke the screen. Rest of it (still) works fine.
Stupid Donkey Kong...
Well, you could donate it to me. 'Tis the season to support your local intern!
Few would agree the sky is blue.
That's because it isn't.
Einstein: Husband, Father, and Lover
But not, apparently, to the same people.