标题： OpenCXD：一个开放的实装设备引导的混合评估框架用于CXL-SSD 显示英文标题

标题： OpenCXD: An Open Real-Device-Guided Hybrid Evaluation Framework for CXL-SSDs

摘要： 计算快速链接（CXL）的出现使固态硬盘（SSDs）能够作为大容量、字节寻址的内存设备参与内存层次结构。这些CXL启用的SSDs（CXL-SSDs）在DRAM和传统存储之间提供了一个有前景的新层级，结合了NAND闪存的密度和类似内存的访问语义。然而，由于缺乏原生支持CXL.mem协议的SSD硬件，评估CXL-SSDs的性能仍然困难。因此，大多数先前的工作依赖于结合CPU模型增强CXL.mem语义和近似内部闪存行为的SSD模拟器的混合模拟器。虽然这种方法适用于早期探索，但无法准确建模对CXL-SSD性能至关重要的固件级交互和低层存储动态。在本文中，我们提出了OpenCXD，一个由真实设备引导的混合评估框架，弥合了仿真与硬件之间的差距。OpenCXD在主机端集成了周期精确的CXL.mem模拟器，并与运行真实固件的物理OpenSSD平台集成。这使得可以通过模拟的内存请求触发固件的现场执行。通过这些贡献，OpenCXD反映了在仅仿真设置中无法观察到的设备级现象，为针对CXL-SSDs的未来固件设计提供了关键见解。 显示英文摘要

摘要： The advent of Compute Express Link (CXL) enables SSDs to participate in the memory hierarchy as large-capacity, byte-addressable memory devices. These CXL-enabled SSDs (CXL-SSDs) offer a promising new tier between DRAM and traditional storage, combining NAND flash density with memory-like access semantics. However, evaluating the performance of CXL-SSDs remains difficult due to the lack of hardware that natively supports the CXL.mem protocol on SSDs. As a result, most prior work relies on hybrid simulators combining CPU models augmented with CXL.mem semantics and SSD simulators that approximate internal flash behaviors. While effective for early-stage exploration, this approach cannot faithfully model firmware-level interactions and low-level storage dynamics critical to CXL-SSD performance. In this paper, we present OpenCXD, a real-device-guided hybrid evaluation framework that bridges the gap between simulation and hardware. OpenCXD integrates a cycle-accurate CXL.mem simulator on the host side with a physical OpenSSD platform running real firmware. This enables in-situ firmware execution triggered by simulated memory requests. Through these contributions, OpenCXD reflects device-level phenomena unobservable in simulation-only setups, providing critical insights for future firmware design tailored to CXL-SSDs.