SSDe: FPGA-Based SSD Express Emulation Framework

Solid State Drives (SSDs) are crucial for modern high-performance computing (HPC) and cloud services, providing superior speed and reliability. Two prominent approaches for mirroring SSD behavior are SSD emulation and simulation. Using specialized hardware, emulation outperforms simulation in speed and efficiency, especially in Hardware-in-the-Loop (HIL) testing and design space exploration (DSE) for cloud service systems. FPGA-based SSD emulation further enhances the accurate emulation of smartSSDs, devices consisting of SSD and FPGA components. Despite their merits, current SSD emulators encounter difficulties meeting these applications' demands. Many are limited by their underlying hardware platforms, impeding their capacity to emulate the full array of SSD behaviors. Some emulators are primarily devised for testing and validating new SSD designs rather than emulating existing, commercially-available SSDs. To address this, we introduce SSDe, an FPGA-based SSD Express emulator that accurately emulates the Non-Volatile Memory Express (NVMe) SSDs. SSDe, a next-generation SSD emulator built on top of FSSD [1] (a previous FPGA-based SSD emulator we developed), brings in additional capabilities such as energy modeling, garbage collection, and runtime reconfiguration. These features enhance its efficiency in managing diverse emulation tasks, making SSDe a more flexible and efficient emulator than both FSSD and traditional software simulators. SSDe achieves an average error of 14.1% in bandwidth and 18% in energy modeling, while its runtime parameter reconfiguration for DSE study takes less than 0.1 seconds (2.36 $\times 10^{5}$ times faster than FSSD). SSDe stands as a new and robust SSD emulator, offering new opportunities for optimizing HPC and cloud infrastructures.