When choosing an SSD for our systems, we are faced with a dilemma: whether to choose SSD architecture with DRAM or DRAMless. We have attempted to conduct a brief analysis based on Silicon Power Industrial's analysis, highlighting their characteristics, advantages and disadvantages:
1. SSD with DRAM:
- Uses DRAM as a buffer between the host and NAND Flash memory.
- DRAM acts as a cache for written data and stores the data mapping table.
- DRAM is 100 times faster than NAND memory.
Therefore, this storage architecture is ideal for enterprise applications with high workloads and a need for low latency and fast read/write speeds.
2. DRAMless SSD:
- Does not use DRAM, so data is written directly to NAND Flash memory.
- The data mapping table is stored in NAND memory.
- In SSDs with NVMe interface, the performance issue can be mitigated with the Host Memory Buffer (HMB) feature, which uses the motherboard's DRAM.
- Advantages: lower power consumption, reduced manufacturing costs, compact size, better thermal management, and greater long-term availability.
- Disadvantages: degraded I/O performance, especially in random writes.
- It is considered a recommended use in embedded applications such as POS and kiosks, where random read operations are predominant.
Popularity of DRAMless SSDs:
Their compact and efficient design makes them ideal for distributed edge computing and connected devices.
In conclusion, we could say that SSDs with DRAM are better for intensive workloads, while DRAMless SSDs are more economical, compact, and suitable for specific applications with lower performance demands.
