I keep reading here and there that flash memory devices, such as pen drives
and camera memory SD cards have a limited number of read/write cycles after
which they can go bad or cause errors. So how about SSD drives? Do they too
have a limited life expectancy?
In this excerpt from
Answercast #21, I talk about how flash memory works on an inexpensive USB
device compared to a drive manufactured as a hard drive for a computer.
SSD life expectancy
Yes, but I want to clarify something first.
- Limited number of read/write cycles is incorrect. It’s a limited number of write cycles.
In other words, the more frequently you write to flash memory, the shorter its lifespan. That’s one of the reasons that you don’t want to use flash memory for things like your paging file, which is constantly written to… and will actually end up shortening the lifespan of that very significantly: specifically on USB flash drives.
People have often asked if they can place their paging file on an external USB flash drive to speed up their system. The answer is yes, maybe for a few seconds after which the flash drive won’t work anymore.
SSD, or Solid State Drives
So, that leads to the second part of this question.
SSD drives are flash memory, but they are different flash memory. They are (to put it kinda crudely) expensive flash memory.
The flash drives that you have, that you might plug in via USB or other kinds of connections, tend to be relatively inexpensive devices. The technology within them is used with the assumption that they’re going to be used significantly fewer times than, say, an SSD drive.
Basically, they’re meant to be mass-produced; to be cheap. That’s why you can go out and get flash drives for less than a buck sometimes. SSD drives, on the other hand (solid state drives), are designed for longer-term use.
The state of Solid State
The technology underneath the SSD drives is always improving. The flash memory that they’re using (the technologies they’re using) is in constant improvement.
The net result is that when you do the math, when you understand how SSD drives now compensate for this particular limitation of a limited number of writes, the fact is that, yes, they will wear out… but typically, they now have lifespans that are (finally) measured in years.
What that means is that it is not uncommon for SSD drives to actually outlive their usefulness.
Either it will outlive the computer or outlive the software, or outlive the person that’s actually using it. The machine itself might be recycled because a new machine comes along.
Solid State Drives are long lasting
So SSD drives are absolutely viable right now. I haven’t tried one yet myself. I’m looking forward to it on my next machine.
The longevity issue has kinda-sorta been dealt with.
Don’t confuse SSD drives (even though they use flash memory) with the cheaper, inexpensive flash drives that are connected via USB. They really are different orders of magnitude in terms of quality and longevity.
Next from Answercast 21- Does an internet installation with a FiOS cable protect my system from possible lightning strikes?