Storage Challenges in AI Data Centers
AI training workloads place unprecedented demands on storage systems: training datasets are growing from terabytes to petabytes and require extremely high sequential read bandwidth; frequent model checkpoint writes demand high IOPS and low latency; and 7x24 continuous operation imposes strict requirements on SSD endurance (DWPD) and reliability.
Against this backdrop, enterprise NVMe SSDs — with performance far beyond SATA SSDs — have become the storage standard in AI data centers. The two mainstream enterprise NVMe form factors on the market today are U.2 and E1.S, each with its own strengths and trade-offs.
U.2: The Mature Mainstream Choice
U.2 (2.5-inch, 15mm thick) is currently the most widely deployed enterprise NVMe SSD form factor. Its advantages include a mature ecosystem with broad compatibility — virtually every server platform supports U.2 hot-swap; a wide capacity range from 960GB to 30.72TB; and proven thermal design, with the metal enclosure providing a good heat conduction path. A representative product such as the Micron 9400 series delivers sequential read bandwidth of up to 7GB/s and more than 1.6 million random read IOPS.
E1.S: The High-Density Form Factor for the Future
E1.S (EDSFF Short) is the next-generation SSD form factor standard driven by the Open Compute Project (OCP). Its core advantages are higher storage density — a 1U server can host 32 E1.S SSDs versus typically 24 for U.2; better cooling efficiency, as the flat profile allows direct air cooling; and standardized power and signal interfaces that simplify data center operations. E1.S is particularly well suited to hyperscale data centers and AI training cluster deployments.
Selection Recommendations and TCO Analysis
Data centers with existing U.2 infrastructure are advised to stay on U.2 to keep migration costs down. For newly built AI training clusters, E1.S deserves serious evaluation: the initial investment is slightly higher, but long-term TCO is better, since higher density means fewer servers and less rack space.
JH Semiconductor offers full lines of U.2 and E1.S enterprise SSDs with capacities from 1.92TB to 30.72TB, along with workload-based selection consulting and performance testing services for customers.