SSD Classification

Classification method:
SSD storage media are divided into two types, one is using flash memory (FLASH chip) as storage medium, and the other is using DRAM as storage medium. The latest is Intel's XPoint particle technology.
SSD based on flash memory:
SSD based on flash memory (IDEFLASH DISK, Serial ATA Flash Disk): uses FLASH chip as storage medium, which is also commonly known as SSD. Its appearance can be made into a variety of styles, such as: notebook hard disk, micro hard disk, memory card, USB flash drive and other styles. The biggest advantage of this SSD solid state drive is that it can be moved, and the data protection is not controlled by power supply. It can adapt to various environments and is suitable for individual users. Long life, depending on different flash memory media. SLC flash memory generally reaches tens of thousands of PE, MLC can reach more than 3,000 times, TLC also reaches about 1,000 times, and the latest QLC can also ensure a life of 300 times. The annual write volume of ordinary users does not exceed 50 times the total size of the hard disk. Even the cheapest QLC flash memory can provide a write life of 6 years. High reliability, high-quality home SSDs can easily achieve one-tenth the failure rate of ordinary home mechanical hard disks.
Based on DRAM:
DRAM-based SSDs: use DRAM as the storage medium, and have a narrow range of applications. It imitates the design of traditional hard disks, can be used by the file system tools of most operating systems for volume settings and management, and provides industrial standard PCI and FC interfaces for connecting to hosts or servers. The application methods can be divided into two types: SSD hard disks and SSD hard disk arrays. It is a high-performance storage that can theoretically be written infinitely, but the only drawback is that it requires an independent power supply to protect data security. DRAM solid-state drives are relatively non-mainstream devices.
Based on 3D XPoint
3D XPoint-based SSDs: In principle, they are close to DRAM, but they are non-volatile storage. The read latency is extremely low, which can easily reach one percent of the existing SSDs, and has a nearly unlimited storage life. The disadvantage is that the density is relatively low compared to NAND, the cost is extremely high, and it is mostly used in fever-level desktops and data centers.