The Lifespan of Flash / SSD

We’ve known for a while that storing projects for more than a couple of years on hard disks which are unplugged is not a good idea; whether they are on a shelf, in a wrapper, or a closet.

However, what I haven’t understood until recently, was the life-span of Flash or SSD media. Last week, I attended the 2016 Creative Storage Conference in Culver City and had a chance to talk with the Micron folks.

The answer to: “What’s the life-span of Flash?” is… “It Depends.”

BACKGROUND

Since films were first invented, production people have tried to explain to producers that, while we can make films that are good, cheap or fast, we can’t do all three at the same time.

In fact, producers get to pick two.

• We can make films that are good and cheap, but they are not made quickly.
• We can make films that are good and fast, but they aren’t cheap.
• We can make films that are fast and cheap, but they aren’t good.

While this is a bit simplistic – for example, we can spend a ton of money and still end up with dreck – these three variables are an excellent way to frame the entire “how do we spend our resources” discussion.

FLASH IS SIMILAR

What I learned was that when engineers design the master wafers from which individual flash and SSD systems are derived, they have several options:

They can:

• Optimize the wafer for speed/performance
• Optimize the wafer for resilience; which gives it the ability to handle multiple reads and writes
• Optimize the wafer for longevity; which gives it the ability to store data with the power off without losing data for long periods of time.

And, like film producers of old, engineers can only pick two.

Since no one buys flash because they want it to be slower than spinning media, performance is always the first choice.

Because flash is still relatively expensive, when compared to traditional hard disks, resilience, which is the ability to read and write data hundreds and thousands of times, becomes the second choice.

What does this mean for longevity? “It isn’t that we can’t store data for a long time on flash, its just that today’s flash is not optimized to support long-term storage.”

AND THE ANSWER IS…

While there is some variation, the consensus of the Micron folks was that storing flash on the shelf, unplugged, would be good for a year or two without losing data. But not long-term.

Sigh… Archiving media is just so difficult!