Earlier this year the IEEE Roadmap and Systems (IRDS) released a technical roadmap report on Mass Data Storage. I was the co-chair on this activity along with Roger Hoyt which included experts on various storage and non-volatile memory technologies. The report is available for free download from the IEEE. This activity is the continuation of a biannual Mass Storage Roadmap effort that Roger and I lead with iNEMI for many years.
The report covers hard disk drives, magnetic tape, optical disc technology as well as solid state storage. In addition, there is material, correlated with other IRDS roadmaps on non-volatile memory technologies such as magnetic random-access memory (MRAM), resistive RAM (ReRAM), ferroelectric RAM (FeRAM) and phase change memory (PCM). There is also a section on the use of DNA for archive storage.
Some highlights from the report follow. Regarding solid state storage, it is dominated by NAND flash, which is currently a $60B market. Alternative technologies such as MRAM, FeRAM, ReRAM and PCM are still more costly per bit but are being used in embedded devices to replace NOR flash and some SRAM (especially MRAM and ReRAM). 2024 is a recovery year for all storage and memory technologies after down years in 2022 and 2023 due to excessive inventories acquired during the supply uncertainties of the Pandemic. Future developments for higher layers and more bits per cell continue with NAND flash, but the cost reductions are getting harder and more bits per cell come with lower endurance and performance.
The figure below shows the NAND flash roadmap from the Mass Storage Roadmap.
The total unit shipment of HDDs continues to decline, with legacy applications being replaced by SSDs. However, the data center and enterprise nearline HDDs market has recovered in 2024 and demand continues to grow for HDD storage for big data applications, including AI. These drives are sealed and filled with helium, have up to 10 disks and may include dual actuators, heat assisted magnetic recording (HAMR) and two-dimensional magnetic recording (TDMR). Current storage capacities are up to 32TB, but 50TB HDDs should be available by 2026. This should allow HDDs to be competitive against SSDs for secondary storage and active archive applications.
The figure below shows some projections for HDD technology from the Mass Storage Roadmap.
Magnetic half inch tape native capacities are currently available up to 50TB (IBM enterprise tape) and tape doesn’t consume a lot of energy except when it is in a drive. Tape is also significantly less expensive per byte of stored data than HDDs. Thus, tape provides a low cost and compact archival storage. Greater than 100TB native capacity cartridges should be available in future generations. Tape benefits from the development of HDD magnetic recording for future capacity increases.
The table below shows projections for magnetic tape from the Mass Storage Roadmap.
Optical disc technology has declined as a consumer media distribution media and the focus on new optical storage products is focusing on their use as a low-cost archival storage media. Write once 100TB optical discs are projected in the near future and optical storage will likely be in optical library systems. Optical libraries face competition from magnetic tape libraries, which are more established for archival applications.
The figure below shows the Optical disc roadmap from the Mass Storage Roadmap.
DNA data storage has been demonstrated in the lab but the costs of reading and writing data on synthetic DNA is too expensive for practical applications. However, because of the rate of technological development of genomics for medical applications, the costs for reading and writing synthetic DNA are dropping and this could make DNA an affordable alternative for archive storage in the near future. DNA storage will probably be in some sort of library system like magnetic tape or optical discs. Much work is needed to create a manufacturable and cost-effective DNA storage system.
Digital storage demand is increasing and this creates a need for more advanced storage technologies to support a robust digital mass storage hierarchy. The IEEE IRDS Mass Storage Roadmap outlines projections for NAND flash, emerging non-volatile memories, HDDs, magnetic tape, optical recording and DNA storage development.
