SSD uses FLASH as the storage medium, and the SATA interface (also PCI-E interface) can give full play to the speed advantage of FLASH . At the same time, it adopts multi-channel technology, which is faster and can reach 400--500MS/s.
Ordinary hard drives are limited by the rotational speed, and the fastest speed is 9000 rpm. The speed is not very fast. It seems that the ideal limit speed is about 100MB/s. Specifically, I forgot that
SATA3 is the interface standard, which can provide up to 6Gbps access speed, but generally not reach. The current SSD generally uses the SATA3.0 interface, and the fastest is about 500MB/S. SSD using PCI-E can reach about 1000MB/S
Three types of hard disks (SSD; HHD; HDD)
Solid State Drive (Solid State Drive):
A hard disk made of a solid-state electronic storage chip array, consisting of a control unit and a storage unit (FLASH chip, DRAM chip). The specification and definition of the interface, the function and the usage method of the solid state drive are exactly the same as those of the ordinary hard drive, and the product shape and size are also completely consistent with the ordinary hard drive. It is widely used in military, vehicle, industrial control, video surveillance, network monitoring, network terminal, electric power, medical, aviation, navigation equipment and other fields.
Advantages: fast read and write speed; shock and drop resistance; low power consumption; no noise; wide operating temperature range; lightweight Disadvantages
: small capacity; limited life; high price
There are also mass storage devices with flash memory modules. Flash handles the most frequently written or restored data in storage. A number of companies are starting to offer variants of the technology, expecting it to be sought after in high-end systems, especially laptops and personal digital assistants.
Hybrid hard drives (HHDs) have many advantages over traditional hard drives, including:
Faster data storage and retrieval in applications such as word processors
Reduced system startup time Reduced
power consumption Reduced
heat generation
Extended hard drive life
Notebooks and PADs Increased battery life
Reduced operating noise level
Disadvantages of hybrid hard drives (HHD) include:
longer seek times for data in the
hard drive More frequent spin changes of the hard drive
Flash module processing failures, making data recovery impossible in the
system total hardware cost is higher
Traditional hard disk (HDD, the abbreviation of Hard Disk Drive):
the English name of the hard disk drive. The most basic computer memory, the computer hard disk
C drive and D drive that are often referred to in our computer as disk partitions are all hard disk drives. At present, the common disk capacities of hard disks are 80G, 128G, 160G, 256G, 320G, 500G, 750G, 1TB, 2TB and so on. Hard disks can be divided into 3.5-inch, 2.5-inch, 1.8-inch, etc. according to their size; they can be divided into 5400rpm/7200rpm/10000rpm, etc. according to the number of revolutions;
the comparison between SSD and HDD
In the past 10 years, the performance of CPU has been improved by more than 150 times. The traditional hard disk has been improved by less than 1.5 times. This uneven development greatly affects the overall performance improvement, especially in terms of I/O. Compared with traditional hard disks, SSDs (Solid State Drives) have no magnetic heads. , Motors, magnetic disks and a series of parts, equipped with NAND Flash chips as storage media, are unmatched by traditional hard disks in terms of running speed, power consumption, and lightness.
At present, traditional hard disks still occupy the main share of the hard disk market due to factors such as low cost. However, with the continuous reduction of the cost of SSD, the continuous improvement of technology and the better support of the system, and the current mainstream notebook computers are also equipped with SATA And the mSATA
interface, including the current Ultrabook (Ultrabook), is only possible to achieve "lighter, faster, lower power consumption, and replace the traditional hard disk in the future."
The most significant advantage of SSD over HDD is speed. For example, it takes 200 milliseconds for an HDD hard drive with 15,000 revolutions per minute to make one revolution . On SSD, since data is stored in semiconductor memory, it can be processed in less than one millisecond . Internally, I/O (input/output) operations are performed on storage units at any location. Therefore, on the most critical I/O performance indicator for many applications - IOPs (that is, how many IO actions per second), SSD can Up to 50~1000 times of HDD hard disk.