We propose LightPC, a lightweight persistence-centric platform to make the system robust against power loss. LightPC consists of hardware and software subsystems, each being referred to as open-channel PMEM (OC-PMEM) and persistence-centric OS (PecOS). OC-PMEM removes physical and logical boundaries in drawing a line between volatile and nonvolatile data structures by unshackling new memory media from conventional PMEM complex. PecOS provides a single execution persistence cut to quickly convert the execution states to persistent information in cases of a power failure, which can eliminate persistent control overhead. We prototype LightPC's computing complex and OC-PMEM using our custom system board. PecOS is implemented based on Linux 4.19 and Berkeley bootloader on the hardware prototype. Our evaluation results show that OC-PMEM can make user-level performance comparable with a DRAM-only non-persistent system, while consuming 73% lower power and 69% less energy. LightPC also shortens the execution time of diverse HPC, SPEC, and In-memory DB workloads, compared to traditional persistent systems by 4.3X, on average.

General purpose hardware accelerators have become major data processing resources in many computing domains. However, the processing capability of hardware accelerations is often limited by costly software interventions and memory copies to support compulsory data movement between different processors and solid-state drives (SSDs). This in turn also wastes a significant amount of energy in modern accelerated systems. In this work, we propose, DRAM-less, a hardware automation approach that precisely integrates many state-of-the-art phase change memory (PRAM) modules into its data processing network to dramatically reduce unnecessary data copies with a minimum of software modifications. We implement a new memory controller that plugs a real 3x nm multi-partition PRAM to 28nm technology FPGA logic cells and interoperate its design into a real PCIe accelerator emulation platform. The evaluation results reveal that our DRAM-less achieves, on average, 47% better performance than advanced acceleration approaches that use a peer-to-peer DMA.

We propose Automatic-SSD that converts all storage management logic into hardware, which enable energy efficient, high performance fast memory based block storage. To achieve low operating power, Automatic-SSD directly reads or writes host-side data to underlying backend storage media without internal DRAM caches. To realize such DRAM-less approach with better performance and make it more energy efficient, Automatic-SSD also removes the internal processor(s) and firmware execution therein by fully automating the backend request management and data transfers over all pipelined hardware modules. We prototype Automatic-SSD on a middle-end FPGA custom board, employing massive numbers of phase change memories as representative of new memory technologies. Our evaluation results show that, compared to a conventional firmware-based approach, Automatic-SSD shows up 28.8× and 25.4× better bandwidth and latency behaviors, respectively, while consuming only 5% of the total energy, on overage.