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SSD Annual Failure Rates Around 1.5%, HDDs About 5%
Lucas123 writes "On the news that Linus Torvalds's SSD went belly up while he was coding the 3.12 kernel, Computerworld took a closer look at SSDs and their failure rates. While Torvalds didn't specify the SSD manufacturer in his blog, he did write in a 2008 blog that he'd purchased an 80GB Intel SSD — likely the X25, which has become something of an industry standard for SSD reliability. While they may have no mechanical parts, making them preferable for mobile use, there are many factors that go into an SSD being reliable. For example, a NAND die, the SSD controller, capacitors, or other passive components can — and do — slowly wear out or fail entirely. As an investigation into SSD reliability performed by Tom's Hardware noted: 'We know that SSDs still fail.... All it takes is 10 minutes of flipping through customer reviews on Newegg's listings.' Yet, according to IHS, client SSD annual failure rates under warranty tend to be around 1.5%, while HDDs are near 5%. So SSDs not only outperform, but on average outlast spinning disks."
Alright, I'll do the math....
9ms average access times on a 7200RPM spinning drive == ~100 IOPS.
High-end SSD: 100K IOPS.
Yes, a thousand times the number of disk accesses. If you're really a developer, you'll see your compile times cut by a factor of 5-10 (depending on how much CPU power you have to spare). Things load from disk like magic.
You don't buy SSDs for the raw capacity, you buy them for the *fast* access times. Period.
Bullcrap. They can be replaced. Look up http://macsales.com/ they sell several sizes for the airs and the pro retinas.
Suppose you were an idiot and suppose you were a member of Congress
Actually, you'd be surprised. The Samsung 840 EVO, a low-cost consumer drive (the high-end is the 840 Pro) that gets down to $0.70/GB, can hit 90K IOPS read on every model, and 90K IOPS write on 500GB models and up.
Sure, older or ultra-cheap drives won't hit that (my new Chronos doesn't get there), but rounding to the nearest order of magnitude will get you 100K IOPS even on medium-end consumer drives.
Wait, you are basing the improvements in compile times on one guy's anecdotal results? Well, here's another: when I switched to an SSD at work my compile times were cut by more than half. It was an huge difference in compile time ie. productivity.
It all depends on your codebase and tools, really. He was probably compiling a relatively small codebase, and for all we know his methodology sucked so a lot of it was in the RAM cache. I can tell you for a fact that a clean build on a large code base was drastically improved.
No he's doing the math right -- At an annual failure rate of 1%, you need to replace 1% of your total capacity every year. With an annualized failure rate of 5%, you need to replace 5% of that capacity overall. The averaging is done because over time, it works out, just like insurance. Sure, on any given year *if* a drive fails, you have to pay for the whole thing, but that's not how one accounts for such failures.
- Michael T. Babcock (Yes, I blog)
Yeah, sure, okay. If you're sitting next to your computer, then yeah, maybe you notice. How about the hundreds of millions of drives that are sitting in a rack somewhere, and will only see a human being twice: Once when it gets installed in the rack, and then only when it stops working for whatever reason and a tech is sent out to replace it.
Hmm, my drives send me emails when they start having problems. (And having gotten one of these emails a few years after setting up the drive initially, I was shocked to find it the email arrived in plenty of time. I pleasantly surprised to find the drive and all data still intact, and had time to swap a replacement into the raid).
Why don't you find out how this is handled by people who actually have hundreds of drives to deal with.
If you let them fail before servicing them you are doing it wrong.
Look into: man 8 smartd
Sig Battery depleted. Reverting to safe mode.
All this discussion on this and no one has commented that TFA is from 2011??
This article isn't reliable information. It's from when SSDs were relatively new and definitely doesn't apply to the in-the-field results people are seeing in 2013.
Reeses
I think he's referring to the power supply in the machine, not just a right out all the lights in your house go off. I've had power supplies that just before they die altogether will flicker on and off repeatedly, that would cause the SSD to flicker as well, causing the issue outlined above.