Types and architecture of solid-state SSD drives
Solid-state drive or SSD is a storage device that operates on the basis of memory chips. Device is mounted master controller for correct function.
Species ssd drives have only two:
- Based on flash memory
- Based on the RAM
Architecture of SSD
This type of solid-state drives are modern developments. NAND memory based on flash memory, which in each device (array of floating gate transistor) stores bits of information.
SSDs can have two types of NAND flash memory: MLC and SLC.
Their difference is that the SLC-device units are arranged in one level, and store only one bit of information, while MLC device can store several bits of information.
Thanks to technology size of MLC drive is small, but at the same time, it can significantly increase the memory and reduce the cost per gigabyte.
Volatile memory are ultrafast retrieving information from its reading and writing. However, such devices are very expensive, so it is often used only for very large database management systems, to powerful graphics workstations.
Usually this type of solid-state storage has additional batteries. If power suddenly lost, it helps to save all the data on the device.
Advantages of solid-state drives
If you want to buy solid state drive, first you need to analyse all of its pros and cons.
The benefits include:
- Fast speed of reading and writing information
- No delay of access to data
- A variety of forms. You can choose SSD different sizes and thicknesses, some of which may even be very thin and even without the protective housing
- No moving parts, unlike a hard disk. Therefore, they do not create vibrations that are insensitive to shocks and substantially more reliable
- Excellent value for the quality-price
- Reading time is always stable
- Low energy consumption
- Opportunities for continuous improvement
- Wide operating temperature range
- Insensitive to electromagnetic fields
Despite the many advantages of these devices can be distinguished, here are several disadvantages:
- Limited amount of overwriting. Most solid state drives allow rewriting 10,000 times or 100,000 times in more expensive option. To achieve this amount, with the drive can only be read, and write it will not be available. Also worth mentioning that the devices are constantly being improved, so soon may leave this disadvantage.
- Price gigabytes on such a device is more expensive than on the hard disk. Therefore, if you go to for reasons of economy, the hard drive will be cheaper to use.
Solid state drives may have completely different form factors. It all depends on where do you want to use them and how much memory do you need.
For everyday use at the home it’s better to buy solid-state drives ssd 2.5 “. Externally, these drives are very similar to the hard disk. Also can be found ssd mini-sized device 1.8 “, but this size is used only when the device can not be completely inserted into the body of 2.5”.
How to install SSDs
To install a solid state drive, most often use the SATA interface. Please note that modern devices work through the channel SATA rev. 3.0.
By the way, it is convenient that the channel support and backward compatibility. That is, if you know that your system does not work with SATA rev. 3.0., it is still safe to buy a ssd drive. Of course, its performance will not be used at full capacity, but still work correctly.
In some cases, the solid state drive ssd can sold with a set of special adapters, brackets. If you have a 3.5 ” it help you to set the device dimensions of 2.5″.
Still on the market you can find devices that are offered in the form of expansion cards and have interface PCI Express. They are used by those who do not give the full SATA features. Then the bus lines are utilized 4 PCI-Express, which can provide data rates up to 2 GB / sec.
To achieve this speed, the drives are often added to the chips to run in RAID-array and 2 controllers.
While that offers a PCI Express on the market are relatively few, but experts have noted its effectiveness, and even this year, many companies expanded their production to include the development of this type of storage.
Mobile users and very small systems for themselves can choose the best SSD -a form factor mSATA.
It works exactly the same as the storage dimensions of 2.5 “, just all the elements of the device are placed very compact.
To install this ssd type has been successful, the motherboard must have a special connector. He also must have an additional channel SATA.
There are drives for external connection. They propose to use with high-speed data transmission bus Thunderbolt. But the cost of such decisions, unfortunately, quite expensive.
And the last group of ssd are devices that are connected externally through a network of Wi-Fi. They have extra batteries, so it is very convenient when moving. After all, you can access your data, no matter where you are. This requires only the Internet
The capacity is varied – from an average of 25 GB up to 2 TB. On the question of what is the best ssd there is answer: able to fit the more data, the greater its value.
Of course, also the price of storage varies depending on this factor, which is limiting for many people.
But in connection with scientific and technological progress and a gradual decrease in the cost of devices, customers increasingly prefer devices that have 240/254 GB.
Here is an example ssd drive huge capacity to solve important industrial applications can serve SSD on PC/104 form-factor, developed Terratel company. This is a very powerful device, which has 3 flash cards, a total capacity of 2 TB.
The controller allows for RAID 0/1/10 functionality and / JBOD.
The model of ssd 2 TB is suggested to use on an industrial scale, medical institutions, telecommunication companies, etc.
More space for domestic use is simply not needed, so drives with a large volume buying specialists for industrial purposes or for special solutions of specific problems.
How do I know the performance of ssd drive? To do this, you need to look at the table of characteristics offered by the seller. There you can find the speed of reading and writing, as well as see the maximum number of records to which the device is intended.
However, do not rely solely on these parameters, because under different conditions of storage may behave differently. Therefore, it is best to not only focus on the technical details, but also to test the device.
What factors affect the performance ssd drive?
First of all, it is a model of the used controller. It determines the bandwidth. His firmware becomes a decisive factor either drive is fast, handles any request for a long time.
No less important are the number and type of flash memory chips, as well as the ability to cache, in which the device works and its capacity.
Another important fact that the ssd performance in any case be consistently higher than the same hard drive. You just need to at least start to load the operating system, as you will notice a significant difference. And so it will be in everything: run a program to install the application: all this is read from the solid-state ssd drive much faster.
Naturally the question of reliability of data storage much care users. After all, if you’re into, vital for the information, it would be desirable to have a guarantee that it will continue. On the one hand, many people are wary that the drive can be used for a limited number of entries. On the other hand, practically achieve this number of records is very difficult.
Plus, the producers necessarily give a guarantee on their products, which reaches 5 years. If during this time something goes wrong with your drive, then its guarantee system, and at the end of this period, the market will certainly have a more modern, fast solid state drive with more performance and capacity. Most likely, you will want to change the device to a more perfect.
It is worth remembering that any device can always something happens, so for reinsurance most important files is still better to keep a backup copy.
Should I buy a SSD?
Interest in SSDs is going last time by chance. Thanks to the SSD device, you can easily greatly increase the performance of any system that is a key factor in the need to update it. Therefore, if you decide to buy ssd, it’s time to do it now. First, determine the size of the device, and then think about the capacity that will be necessary for you.