Slashdot Mirror
Toshiba To Launch First 512GB Solid State Drive
designperfection9 writes "Toshiba said Thursday that it will show off a new line up of NAND-flash-based solid state drives with the industry's first 2.5-inch 512GB SSD.
The drive is based on a 43 nanometer Multi-Level Cell NAND and claims to offer a high level of performance and endurance for use in notebooks as well as gaming and home entertainment systems."
Random writes are problematic for SSDs because Flash memory writes are done in two steps: erase and write. The erase step always blanks a relatively big block of Flash memory, so to write a 4K sector, a big block of Flash memory has to be read, erased and then written back with the modification. Randomly writing small blocks is therefore several times slower than continuous writes.
As an example, 150GB solid state hard drives are selling around the $7-800.00 US range on Newegg.com
I think you mean that 250GB SSDs are in the $700-800 range.
128GB (the closest I can find to 150GB) are around $250-350.
Actually, most of the SLC SSD drives are fairly immune to the random write stall issue that plagues MLC drives. For example, compare SLC and MLC drives from OCZ. The older OCZ Core SSD drives (SLC) have much faster random write access than newer OCZ Core V2 SSD drives (MLS) even though the Core II have much higher specified/published (sequential) write speeds.
OCZ's official line on the frightening performance problems with random writes on MLC drives (i.e. multi-second system stalls and random write throughput as low as 4 writes/second) is "we encourage potential customers to research this product and insure that it will fill their needs. These MLC based drives have extremely fast reads, and if you need a drive with fast sequential (frequent) writes, please check into our SLC based SATA II drive series."
At least OCZ is somewhat honest up front in acknowledging that their MLC drives are not for everyone. But FWIW, nearly all MLC SSD drives are orders of magnitude for real world performance (that includes writes) than their sequential performance specs would suggest.
Currently, the Intel drives are the only shipping MLC drives with good random write performance out-of-the-box. OCZ has announced (but is not yet shipping) a new "Vertex" series SSD that combines MLC with 64MB of RAM cache that speeds up random writes tremendously.
But in general, right now, it's buyer beware if you need fast random write access for higher system performance (i.e. a Windows user). Make sure you get either one of the Intel drives (MLC or SLC) or a well known SLC drive if you're concerned about anything other than strict read performance. Before you buy a MLC drive, follow OCZ's suggestion and do a lot of research on the drive first.