In-memory key-value store (IMKVS) has gained great popularity in data centers. However, big data brings great challenges in performance and power consumption because of the general-purpose Von Neumann computer architecture. Remote direct memory access (RDMA) technology supporting zero-copy networking could partly alleviate the problem but is still not efficient for KVS. To overcome this problem, we present a flexible and ultra-low-latency IMKVS system named FULL-KV, based on a CPU-FPGA heterogeneous architecture. The FPGA serves as a KVS accelerator that can bypass the CPU and implement both the network stacks and the KVS processing with a highly parallel hardware architecture. The system latency of FULL-KV can achieve as low as 1.5μs/2.2μs for the PUT/GET operation, which is 3.0x/1.5x faster than current state-of-the-art hardware-based KVS systems. Besides, FULL-KV can support 4x larger values (up to 4M bytes). Given a total Ethernet bandwidth of 20Gbps, the peak throughput of the single-node FULL-KV can reach 26.0 million key-value operations per second (Mops). In the two-node test system with a commercial Ethernet switch, the peak throughput can reach 52Mops, manifesting the system scalability and practicability.

中文翻译：

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FULL-KV：基于 CPU-FPGA 的灵活且超低延迟的内存中键值存储系统设计

内存键值存储 (IMKVS) 在数据中心中广受欢迎。然而，大数据由于采用了通用的冯诺依曼计算机架构，在性能和功耗方面带来了巨大的挑战。支持零拷贝网络的远程直接内存访问 (RDMA) 技术可以部分缓解该问题，但对于 KVS 仍然效率不高。为了克服这个问题，我们提出了一种基于 CPU-FPGA 异构架构的灵活且超低延迟的 IMKVS 系统，名为 FULL-KV。FPGA 充当 KVS 加速器，可以绕过 CPU 并通过高度并行的硬件架构实现网络堆栈和 KVS 处理。对于PUT/GET操作，FULL-KV的系统延迟可以达到低至1.5μs/2.2μs，即3.0x/1。比当前最先进的基于硬件的 KVS 系统快 5 倍。此外，FULL-KV 可以支持 4 倍大的值（最多 4M 字节）。在以太网总带宽为 20Gbps 的情况下，单节点 FULL-KV 的峰值吞吐量可以达到每秒 2600 万次键值操作（Mops）。在带有商用以太网交换机的两节点测试系统中，峰值吞吐量可以达到52Mops，体现了系统的可扩展性和实用性。