SSDs work by storing bits in a special type of transistor. When you write a bit to the SSD, it only takes one transistor to store that bit, not two like an ordinary hard drive:
Now imagine you have a group of N transistors, and if you want to write a bit to the SSD, what you have to do is take some of these transistors and turn them off so that all of them are empty and then turn on N new transistors. This is a very slow process and it’s called wear leveling. Wear leveling is the reason why after about 10 years with your SSD, the performance will be about 90-95% of that when new.
Because SSDs are so new and rapidly evolving, there is a lot of information that is not yet widely available. That’s where we come in. We’ve tried to distill the important concepts into something we hope is both useful and accessible.
Don’t try this at home. Some of the stuff on this blog is still in an early stage, and may even be inaccurate. There may be things in here we don’t fully understand ourselves yet, either. This sort of thing happens when you write about something that’s new and evolving quickly.
The Solid-State Drive (SSD) is the new kid on the block, replacing traditional hard drives. The performance of SSDs on the market is up to 50x that of a traditional hard drive with more than 70% cost reduction.
Solid state drives, or SSDs, are the future of data storage. They’re basically flash memory chips that can be read and written a million times faster than a standard hard drive.
SSDs are better in some ways, worse in others. But they cost more than hard drives, so some people are asking whether it’s worth paying more to get them.
The answer depends on how you want your data to behave over time. For example, do you care if the drive is as fast as possible or if it doesn’t wear out?
If you want your data to be good as long as possible, you’re going to hate this: SSDs don’t get much faster. In fact, after five years they stop getting faster at all. If you’re using your SSD now and plan to keep it for five years, update: 10 years , don’t buy a new one until you need one. If you buy an SSD today, it will probably still work just fine in five years even though there will be no further improvement in performance at that point.
If you want your data to wear out as fast as possible, the answer is simple: Stay away from SSDs and go into a store that sells hard drives and buy one right now with plenty of
In computing, a solid state drive (SSD) is a non-volatile computer storage device that uses solid-state memory to store data persistently. SSDs are distinct from flash memory and other forms of NVM. In computing, the term “solid state” usually refers to any form of memory (e.g., RAM) that does not rely on a mechanical, magnetic or electrical mechanism for storing or retrieving data. Solid state storage is available in many different types, speeds and capacities, from small-capacity devices used in digital cameras and handheld devices to enterprise-class products with capacities exceeding 1 terabyte (TB), the equivalent of 1 billion gigabytes.
In contrast with traditional spinning disk drives, an SSD has no moving parts and typically uses integrated circuits or other non-volatile memory technologies. Unlike magnetic disks, SSDs do not use disk platters; rather their memory is formed into blocks of circuits, referred to as cells or pages. These blocks are electrically connected to each other and to the control circuitry that manages data access, so that when one cell is written to the data is stored in all connected cells.
SSD memory does not lose data when power is lost because all information is retained by the electrical connections between cells. The major
Investing in a solid-state drive (SSD) is risky.
The technology is new, and it is still evolving. The storage capacity of SSDs has improved by a factor of ten or more in the past few years, but there are many technological variations among the various models. The one we use at work has a much smaller number of NAND flash chips than some other drives, which means it has a shorter lifetime and lower reliability. This is partly due to manufacturing tolerances, but mostly because it uses less flash memory overall.
The price of SSDs varies widely, because production costs are very high and demand is low. But that doesn’t mean you should buy one if you see one on sale at a discount price–especially if it’s not what you need; that’s called “purchasing power.” Even if your needs are modest, buying more than you need can mean having to store stuff you don’t want anymore or pay for storage space you don’t use.
This is not the place to discuss this risk systematically; our purpose here is simply to explain how SSDs work and how their volatility interacts with other factors affecting investment decisions.
The main purpose of a solid-state drive (SSD) is to offer high performance, reliability and long-term endurance. To achieve these goals, a drive must be able to withstand the forces applied by the head moving in and out of the disk. The head contains a magnet with an extremely fine tip that is used to read and write data on the disk surface. The direction of the head’s motion determines the force applied on the disk surface, which creates a physical wear pattern on it.
The actual amount of wear depends on many factors, but one of the most important ones is the amount of thermal expansion due to changes in temperature. When a drive is new, it has very low resistance and is made from very hard materials such as tungsten or tantalum nitride. Once it’s been used for some time, however, this resistance increases due to microstructural changes and oxidation at the contact points between the disk and platters and between platters.
To prevent this increase in temperature from causing excessive wear, an SSD manufacturer moves all its components closer together, reducing their overall size. This reduces all of these components’ contact with each other and therefore their thermal resistance. In addition, manufacturers apply various techniques to spread out heat generated by mechanical components over