Super large capacity has become a major competitive advantage of HDD disks, and several major hard disk manufacturers are also chasing each other on this point. If you want to increase the capacity of a mechanical hard drive from the internal structure of a traditional hard drive, you need to start from two aspects. The first is to increase the capacity of a single disc, and the second is to increase the number of discs. Look, in order to increase the capacity of a single disc, it is necessary to optimize the arrangement of the magnetic media on the disc. In the CMR (traditional magnetic recording) technology, the PMR (perpendicular recording) technology is the most widely used and mature one. kind. The advantage of PMR is that the magnetic media can be evenly arranged on the disk, and the reading and writing are very accurate. The disadvantage is that when the disk area remains the same, the capacity of a single disk is limited, and there is not much room for improvement.
Toshiba released a 1TB 2.5-inch single-platter hard drive (MQ04ABF100) with a thickness of only 7mm. Perhaps there have been similar products before, which did not attract much attention, but it is worth noting that this is the first to use Showa Denko The ninth generation of vertical storage technology.

In the HDD field, Japanese electronics companies have played a very important role in the supply of spare parts. In addition to supplying TDK for magnetic heads and disks, Showa Denko is also a very important HDD component manufacturer, and this technology can increase the capacity of 3.5-inch hard disk disks. Increase to 1.5 ~ 1.8TB, as an old friend and long-term partner of Dongyi, it is natural to get the first month. On the other hand, Toshiba’s GMA technology has also been updated to the second generation. Wu Boshen, senior manager of the storage product market at Toshiba Electronics (China) Co., Ltd., introduced that Messenger has added a micro-movement based on the previous magnetic head, which can control the movement of the magnetic head more precisely. position to ensure the stability of reading and writing. At the same time, with the maturity of technologies such as ammonia filling and Toshiba laser welding, the new king of the capacity arena, Toshiba's 14TB ammonia hard drive, finally made its debut in Beijing. In terms of specifications, MGO7ACA14TE has a capacity of 14TB, 9 disks and 18 heads filled with ammonia, and a single disk is about 1.56TB; MGO7ACA12TE has a capacity of 12TB, 8 disks and 16 heads filled with ammonia, and a single disk is 1.5TB. Both rotate at 7200RPM and are equipped with 256MB cache. They use SATA 6Gbps interface. In terms of performance, the read and write speed of 14TB is 260MB/S, the read and write speed of 12TB is 250MB/S, and the MTBF is 2.5 million hours. The energy consumption of the time state is 7.6WV and 4.6WV respectively.

Wu Boshen said that the main reason is cost considerations. Compared with air hard disks, the cost per GB of 10TB ammonia hard disks is still much different, and data center users have some optimization needs for the overall TCO, so Toshiba’s 10TB products Admiral air hard disk has reached its limit, and when it reaches 14TB, air hard disk technology can no longer support such a large capacity, so it switched to ammonia hard disk technology to provide cloud-level and enterprise storage solution providers with the required energy saving features and storage density to help them meet their TCO goals. At present, enterprise servers and storage customers are aware that the use of SMR technology can effectively increase the capacity of hard disks. This is because SMR technology allows magnetic media to be stacked and arranged like tiles. Can accommodate a little more magnetic media. But there is a problem, because the magnetic head of the hard disk is that the writing head is larger than the reading head, when writing (N) tracks on the SMR stacked track, the following track N+1) will also be "accidentally" written. Sequential writing does not affect, but when writing randomly, in order not to cause data loss, if you want to modify the data of (N) tracks, the hard disk must first check the original data of (N+1) tracks (read ->write) to another track->write track (N)) to move the original N+1) data back to the original position. This has an impact on performance. Therefore, SMR is more suitable for read-more-write-less (WORM) scenarios.
In short, SMR technology can indeed ensure that the capacity of a single disc has been increased, but in the current mainstream practical application process, the effect is not as good as that of hard drives using CMR technology, and at present, many cloud storage and gigabytes of data The center does not yet have good support for SMR hard drives at the software/hardware level. It just so happens that Toshiba is a very pragmatic company. Based on more user feedback information, it has been decided that the MGO7ACA series does not use SMR shingling, which is often used in high-capacity hard drives, to maintain traditional CMR recording. The user's storage needs.