FOSDEM 2023, Brussels / Feb 5, 2023
Computational storage devices (or CSDs) are the new emerging technology that allows offloading computation to storage devices. In this technology, computation is pushed to the storage device (close to the data), and only the final result is returned to main system memory. The efficiency and performance gains come from the reduction in data movement over the I/O interconnects, thus relieving pressure on the memory bandwidth in the traditional Von Nuemann architecture where all data is first moved to the main memory before processing. Despite lots of enthusiasm, proposals, and research publications, there are no immediately available open-source ready to use CSDs available. Due to the lack of such prototypes, it is very hard and challenging to explore hardware, physical interfaces, application APIs (block-level, file system, key-value stores) for CSD devices. In this talk, I will present OpenCSD, a completely open-source CSD exploration platform designed with QEMU. OpenCSD uses eBPF as the means to offload computation to the CSD, and includes an accompanying file system. FluffleFS, the file system, uses POSIX extended attributes to interact with the CSD device. The full, open-source implementation including a block-device, programming toolchain and a file system interface; allow anyone to explore the paradigm of computational storage.