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We're at a point where regular hard drives are ridiculously cheap $60-80 for 2TB (2.9c - 3.9c per GB), while regular SSDs are $1.5-$2 per GB. There's a huge ga

• Nrsolis 15y ago
  One of my biggest questions is the lifetime of these drives. I know that flash memory has a certain number of write-cycles but has there been any study done on how long these drives last in an almost constant write environment like OLTP?
  • pmh 15y ago
    IIRC, SLC NAND has ~100,000 write cycles and MLC ~10,000 (enterprise-level SSDs almost exclusively use the former). I'm not aware of any recent studies specifically on durability, but given that there are no moving parts I'd imagine that SSDs last at least as long as mechanical drives. There's also this bit from the press release: "[The] 700GB drive [is] able to write 28 terabytes of data every day for five years."
    • wtallis 15y ago
      There's a big tradeoff between reliability and density: 50nm MLC is good for around 10k cycles, but 34nm and 25nm MLC are rated in the 3k-5k range, and it's not clear yet whether 20nm MLC will be able to stay in that range. SLC is much more reliable, but also much less dense than MLC. It's easy to maintain overall device reliability (and performance) by having more spare area, but that negates a lot of the benefit of moving to a smaller process. (And the performance penalty from having fewer flash chips to stripe across for a given drive size also detracts from the smaller process size.)
  • rektide 15y ago
    Warranty is key here. That and having prepared ops. Which is no different than it was with HD's. But for the sake of it, let's run the numbers. A 700GB drive being written at 2GB/s would fully cycle in 350 seconds. That's 86400/350 is 247 cycles a day (amusing 247 ~ 24/7 coincidence spotted). Assuming a 10,000 cycle life, that's 40 days of operation. Go to 100,000 cycle life and that a 400 day lifetime of non-stop full-speed writing. And worth every sweet cent of that somewhat short life, in this commenters opinion. I'm sure that the half rack of HD's it'd take to get this kind of IOPs wouldn't have an in any way improved expected lifetime cost. If you just need throughput the story may be a little different.
  • modeless 15y ago
    "The P320h drive also provides enterprise-class levels of endurance with the 700GB drive able to write 28 terabytes of data every day for five years." Not only that, but the write endurance failure mode is benign: the drive simply becomes read only.
• nodata 15y ago
  > Hybrid SSD/HDD drives were supposed to fill that niche, but they are still pretty crappy, they don't really solve any HDD problems. Hybrid drives aim to bring together the (cheap) capacity of hard drives and the speed of SSDs.
  • rorrr 15y ago
    And they fail at both.
• johngalt 15y ago
  Hybrid drives won't take off. Just hit the history books. It's not like there were hybrid tape/HDD drives. When a technology like this comes along it will slowly marginalize the old gear. So my crystal ball predicts the adoption of tiered setups. Anything that needs the performance bad enough to justify the cost will buy SSDs. HDDs will slowly be pushed into secondary "bulk storage" roles, then finally to backup and archival.
  • nitrogen 15y ago
    It's not like there were hybrid tape/HDD drives. Actually, for a long time if you requested aerial image data from the USGS, an automated tape library would copy the desired data to hard drive, and then you could download it. It was always hard to find that site (obviously you don't want Google crawling a tape library), and I can't find it now if it still exists. Granted you may have been referring to actual integrated hardware, but I think such an automated system is close enough.