Solid state drives or SSD’s have come a long way evolving rather swiftly when compared to the traditional hard drives. Word is that one day SSD’s will replace conventional hard drives ruling the roost. Marking an SSD as your priority storage medium would mean your interests lie at making your computer performance oriented. While SSD vanquishes the territory of efficiency, speed, and compactness, there has been a lot of buzz around the reliability and durability standpoint as it can only withstand a certain amount of reading and write cycles. Here’s a brief insight into the evolution of SSD and its architecture to get a better understanding of this ambiguity:
DRAM:
Dynamic Random access memory or (DRAM) was the primeval member in the family of SSD’s. Dynamic RAM’s store each bit explicitly on a capacitor integrated on a circuit. Each capacitor in the circuit can be charged or discharged accordingly to represent corresponding binary 1’s and 0’s. As the charge on a capacitor is subjected to leakage, the data saved on the DRAM is lost within the stipulated time. Due to the following reason, this ancestor of SSD’s ceased to be used as a means of the permanent storage device.
Incorporation of Flash in SSD’s:
A flash memory in layman’s terms is a memory that is similar to a pen drive. A flash memory can be erased electrically and hence is a non-volatile storage medium. 1984 marked the usage of EEPROM in memories; nevertheless, a writing program required a complete erase of data on the EEPROM. This led to the invention of flash-based SSD’s. Flash-based solid state drives enable data to be manipulated at the page level and hence making the read and write more convenient. A flash-based SSD can be subdivided into two types: NAND-type and NOR type. NAND type flash memories are widely preferred for their properties and contribute to a major portion of SSD’s manufactured.
ARCHITECTURE:
A solid-state drive primarily comprises a controller, memory, battery, cache, interface.
The controller acts as a bridge for communication between the memory and the computer. A controller is responsible for the execution of code at firmware level and has other functionality as mentioned below:
- Allocating temporary space for reading and write operations
- Mapping of bad sectors
- Avoid wearing of memory blocks etc.
A memory generally a NAND based flash memory is widely preferred by manufacturers for its durability rather than its speed. A memory is segregated into blocks and each block is segregated into pages.
To ensure a smooth read and write operation on each block/page a memory incorporates the usage of temporary memory called cache which saves the intermediate information when a large amount of parallel read and write operations take place. The information of cache is manipulated by the controller.
A battery sometimes a capacitor is used to back the cache for flushing the data into memory in case of abrupt power loss.
An interface is the physical bus or connector line which connects the computer and the SSD. There are several interface standards available and the interface has a great influence on the transfer speeds of data. Examples of a few interfaces are Serial ATA, PCIe, Parallel ATA, USB etc.
After a comprehensive look at the architecture we are now in a superior state of understanding to get a lucid perspective on SSD failures and their indications:
- Hardware Failure/ component failure of an SSD: Hardware failure would mean the device is showing abnormalities when powered. Most of the times such a failure can be studied by connecting the SSD to different computers or by using a different cable. Any indications of this failure would be the flickering of power indicator (if any) or the drive not being detected. The interfaces like SATA decrease the transfer or signaling rate between the drive or the computer when a lot of errors are being reported to avoid loss of data, this can also be one of the major indicators of a dying drive.
- Failure due to physical damage/ thermal shock: It is quite normal for electronics to turn faulty when exposed to any kind of physical stress, No wonder most of the electronics have a handle with care caution. Fortunately, unlike an HDD these drives may endure physical abuse but any damage in circuitry cannot be disregarded and can have data loss consequences.
- Failure due to degradation and corrosion: The prime adversary for an SSD’s longevity is corrosion. These failures cannot be perceived until we get a proper look on the internal circuitry. However, they can be avoided by maintaining a virtuous routine.
- Bugs in flash drive’s firmware resulting in corruption or over-writing of data: Frequent loss or corruption of data is the prime indicator of this kind of a failure. Contacting the manufacturer at the earliest would be the best way to avoid any further loss. The errors at firmware level also alter the internal communication process of the control system and cause a corruption of data when information in the cache is not completely transmitted.
- Partial failure due to bad blocks affecting the efficiency: The unit on memory at which erase operations are performed is called a block. A lot of drives are transported from a manufacturer with bad blocks, these blocks are marked as bad by the manufacturer itself. During the deployment as well, a drive can develop bad blocks. Increase in the number of bad blocks would indicate the parallel decrease in usable space on the drive.
SSD’s usually do not give any warning signs as they near failure. When an SSD fails, it no longer works and hence results in huge data loss. What to do when SSD fails that results in huge data loss? In such case, it is really a nightmare task to perform data recovery from failed SSD. However, no need to worry in such situations, as data recovery from failed SSD is still possible with advanced data recovery programs.
Remo Recover is one such data recovery program that recovers data from failed SSD drives on both Windows as well as Mac based platforms, as the software comes out with Windows and Mac versions. Download the demo version of the software and get back your files from the failed Solid State Drive successfully.
