Advances in flash technology have benefited the data center. Increasing tier counts and increasing vendor reliance on triple-level (TLC) and quad-level cells (QLC) have contributed to a virtual doubling of SSD top-line capacity every few years. Data centers looking to optimize storage capacity on a rack-by-rack basis find these top-tier SSDs to be an economically wise investment from a TCO perspective.
Solidigm was one of the first vendors to introduce 32 TB class enterprise SSDs several years ago. The D5-P5316 utilized Solidigm’s 144L 3D QLC NAND. The company is very bullish on his QLC SSD in data centers. Compared to other flash vendors, the company continues to use floating gate cell architecture while others move to charge trap configurations. A floating gate holds a programmed voltage level for a longer period of time compared to a charge trap (there is no need to “refresh” the cell and the read window is much longer). The tighter voltage level retention feature of NAND architecture helped Solidigm bring his QLC SSDs to the enterprise market.
Source: Advantages of Floating Gate Technology (YouTube)
Solidigm claims that its 192L 3D QLC is very competitive with its competitor’s TLC NAND currently on the market (see Samsung’s 136L 6).th Gen. V-NAND and Micron’s 176L 3D TLC).
Solidigm categorizes QLC data center SSDs into “Essential Endurance” and “Value Endurance” lines. Back in May, the company introduced his D5-P5430 as a drop-in replacement for his TLC workloads. At the time, the company hinted that it would launch a new “Value Endurance” SSD based on 4th generation QLC flash in the second half of this year. His recently announced D5-P5336 is the company’s latest and greatest “Value Endurance” line.
The D5-P5316 used an indirect unit (IU) of 64KB (compared to the 4KB used in typical TLC datacenter SSDs). Endurance and speed were acceptable for certain kinds of workloads that could avoid writing less than 64KB, but Solidigm decided to remedy the problem by choosing his 16KB IU on the D5-P5336. bottom.
The increased tier count allows Solidigm to offer D5-P5336 with capacities up to 61.44 TB. This caps the maximum capacity crown for a single NVMe drive, allowing a single 1U server with 32 E1.L versions to reach 2 PB. For a 100 PB solution, Solidigm claims up to 17% lower TCO compared to its competitor’s highest capacity (after factoring in number of drives and servers, as well as total power consumption).
|Solidigm D5-P5336 NVMe SSD Specifications
|Solid Digum D5-P5336
|2.5 inch 15mm U.2 / 7.5mm E3.S / 9.5mm E1.L
|PCIe 4.0 x4 NVMe 1.4c
7.68TB, 15.36TB, 30.72TB, 61.44TB
7.68TB, 15.36TB, 30.72TB
15.36TB, 30.72TB, 61.44TB
|3D NAND Flash
|Solidigm 192L 3D QLC
|Sequential performance (GB/s)
|128KB Read @ QD 128
|128KB write @ QD 128
|Random access (IOPS)
|4KB read @ QD 256
|16KB write @ QD 256
|Latency (typical) (us)
|4KB read on QD 1
|Write 4KB on QD 1
|Power consumption (Watts)
|128KB sequential read
|128KB sequential write
|4KB random read
|4KB random write
|100% 128KB sequential write
|100% 16KB random write
|0.42 (7.68TB) to 0.58 (61.44TB)
Note that Solidigm emphasizes workload endurance and performance numbers tailored to IU. The product brief is still in development, so many interesting aspects are still unknown.
After all, the race for the capacity crown comes with tradeoffs. Similar to hard drives that employ shingled magnetic recording (SMR) for extra capacity at the expense of performance for a wide variety of workloads, Solidigm uses QLC NAND optimized for read-intensive applications. 16KB IU equipped. Given the large capacities per SSD, many data centers find it perfectly acceptable (at least in terms of endurance) to use SSDs for other workloads where storage density requirements are more important than write performance It is considered possible.