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How Intel and Micron May Finally Kill the Hard Disk Drive
itwbennett writes: For too long, it looked like SSD capacity would always lag well behind hard disk drives, which were pushing into the 6TB and 8TB territory while SSDs were primarily 256GB to 512GB. That seems to be ending. In September, Samsung announced a 3.2TB SSD drive. And during an investor webcast last week, Intel announced it will begin offering 3D NAND drives in the second half of next year as part of its joint flash venture with Micron. Meanwhile, hard drive technology has hit the wall in many ways. They can't really spin the drives faster than 7,200 RPM without increasing heat and the rate of failure. All hard drives have now is the capacity argument; speed is all gone. Oh, and price. We'll have to wait and see on that.
Well, the Samsung 3.2 TB drive claims that you can read/write the entire drive every day for five years before failure.
Such statistics are meaningless in my book. Light bulb manufacturers claim their bulbs will last five years or seven years but when you look at the fine print they say that's given under the idea you're turning the light on, leaving it running for 3 hours, and turning it off once per day -- nobody uses light bulbs like that.
Under common usage patterns, you can expect up to 25 years life for first-gen SLC, 15 years for first-gen MLC, 10 years for current-gen MLC, 5 years for current-gen TLC. MTBF is lower due to defective cells and such, but that's also true for HDDs.
More accurately, recent versions of OSX have their use of TRIM commands limited to the 'apple endorsed' models of SSD, the ones the machine ships with. There's some dispute over the reasons for this. One faction claims it's Apple trying to sabotage upgrades, making it so that if you buy an after-market SSD rather than paying their insane markup performance will become awful. Another faction claims it isn't deliberate sabotage, but rather a lack of interest in testing for unsupported hardware configurations: TRIM can potentially malfunction horrible if the SSD doesn't impliment it in quite the expected way, and Apple has only coded and tested it for their preferred models. By disabling it on third-party hardware they remove the need to test for fifty-odd different devices to make sure it isn't going to corrupt data.
Remember that a flash memory does not hold data forever. Unplug it for a year, and all data is lost. It is like a dynamic memory, with retention in weeks, not milliseconds. As long as a controller keeps refreshing data, you are OK - subject to a limit on rewrites, which few of us will ever reach.
Also incorrect assertion that drives don't go faster than 7200 (there are 15k drives, just they are pointless for most with SSD caching strategies available).
With Enterprise SSD drive prices hitting $1/GB (granted some are still $2-3/GB), the days of 15k RPM drives are definitely numbered. You get 50-100x the IOPS out of SSDs compared to the 15k RPM SAS drives. That means for a given level of IOPS that you need, you can use a lot fewer drives by switching to SSDs.
I'd argue that if you are short-stroking your 15k SAS drives to get increased IOPS out of the array, it's past time to switch to enterprise SSDs.
Wolde you bothe eate your cake, and have your cake?