The influence of disk trends on storage industry

Trends of Disk Drives

Looking at the influence of disk trends on storage industry in recent years, with the development of the Internet, the market demand for data storage has also increased. Especially for the speed and convenience of SSD which has greatly increased the demand for solid state drives. But high-performance products come with high prices at the same time.

The Internet popularization produced a large number of archives containing various forms of data and accumulated as the amount of data was quickly replicated. The technology of hard drives must evolve at an alarming rate to meet the demand for storage space.

Especially in the data center, the market scale grows at a rate of more than 10% per year. With the trend of digitization of the masses, personal photos, files and information require more storage space to accommodate.

The solution to return to storage space, although Hard Disk Drive (HDD) can already store a large amount of data, but the reading speed is too slow, the experience is not very good for consumers. In contrast, solid state drives (SSD) that read several times faster are the better solution. (Please refer to HDD vs. SSD – What’s the difference)

2018 SSD has been widely used in notebook and personal computer storage devices, with a speed that is several times faster than traditional mechanical hard disks, enabling fast reading and writing of data. However, SSD still has a big gap between the price and the mechanical hard disk. The data rescue technology is not mature enough to replace the mechanical hard disk in all applications in a short time, such as the stable market of enterprise storage industry.

What is SSD?

The storage medium of most solid-state hard disks is a kind of flash memory, also known as NAND-Flash. The principle is to store data (that is, 0 and 1) in a memory cell array composed of floating gates (FG). Inside, since the FG is electrically independent of the insulating layer, the incoming electrons are trapped inside.

Under normal conditions, the charge will not escape even after many years, and the purpose of storing data without the power supply of the memory is to become a storage method to replace the traditional hard disk.

However, the shortcoming of flash memory is that during the long-term operation of the solid-state hard disk, the insulation layer will be erased many times, and it will gradually become thinner over time. It is likely that there will be leakage or even damage, which is why SSD is generally considered to be the reason for the short life.

SSD Type Innovation

In the data storage industry, by dividing the potential of the smallest physical storage unit in the flash memory into different orders, one to four bits can be stored in one storage unit memory, and the bits can be stored according to each unit (Cell). The number of bits can be divided into SLC (Single-level cell, SLC), MLC (Multi-level cell, SLC), TLC (Trinary-level cell, SLC), and the latest QLC (Quad-level cell, SLC). .

In a single-level cell (SLC) device, each cell stores only one bit of information. Multi-level cell (MLC) devices allow each cell to store more than one bit of data by controlling multiple charge values.

The most common TLC (Trinary-Level Cell) is available on the market. Each unit can store up to 3 bits of capacity (3 bits/cell), so there are eight different voltage states. Compared to SLC (only 1 bit can be stored) and MLC (only 2 bits can be stored), more data can be stored in the same volume, so the capacity is larger and the cost is lower – a single unit can store SLC three times The amount of information, the TLC era also symbolizes the popularization of SSD.

By analogy, QLC (Quad-Level Cell), as its name implies, is to increase the storage unit of each unit to 4 bits (4 bit/cell), and the voltage status has also increased to 16 types. Compared with TLC, you can store 33% more data to achieve lower cost and larger capacity.

But in contrast, QLC’s reliability, longevity and power consumption performance will be worse than TLC, but some manufacturers claim that QLC technology can achieve about 1,000 times of erasing, plus a five-year warranty, should be enough to cope with consumers’ weekdays. Demand, and low prices, is enough to attract more industries that pursue efficiency. The current 2.5-inch SSD, with a capacity of up to 30TB or more, has approached or even surpassed the HDD’s single storage capacity, symbolizing the high-capacity and low-cost SSD era.

In addition to the lower standard consumer market, QLC SSD will soon expand to the enterprise and data center markets. The existing SSDs are difficult to rescue due to longevity and reliability concerns, and the data center does not use SSD. Store important data, but use it for ultra-high-speed storage applications such as data operations, media file transfers, streaming, and more.

At present, the reliability and life of QLC have not been verified by actual use. If you are considering users who are trying to use large-capacity QLC SSDs, look forward to a new era of cheap and efficient storage!

The change of storage industry – Why choose SSD array (All-Flash Array) from now?

QSAN Technology, Inc. launched the XCubeFAS XF2026D All-flash array in June 2018. With the build-in QSLife feature, XF2026D solves the most worrying SSD life monitoring problem of most users. QSLife can record and analyze the behavior of SSD and monitor the current status and usage of SSD. It also provides an early warning function for SSD remaining life and health status.

Alex Shih is a product manager of QSAN Technology, Inc. You can contact him at alex.shih@qsan.com.