Scalable Resource Disaggregated Platform That Achieves Diverse and Various Computing Services

ion magem nt Services Physical Layer logical Layer Service Layer router server appliance Future technology for NEC’s C&C cloud platforms Scalable Resource Disaggregated Platform That Achieves Diverse and Various Computing Services NEC Technical Journal/Vol.9 No.2/Special Issue on Future Cloud Platforms for ICT Systems 72 ExpEther expands the PCIe switch chip virtually over the Ethernet by extracting the chip’s internal bus and exchanging it over the Ethernet. In a virtualization, the Ethernet is transparent to the OS and software. Therefore, the ExpEther chips connected via Ethernet are recognized as a standard PCIe switches. As a result commercially available hardware, driver software, and Ethernet switches can be utilized as is without any modification (Fig. 3). Because all the functions of the ExpEther are implemented in a chip (ASIC, FPGA), the access delay of PCIe devices including the ExpEther chip and the Ethernet switch, is suppressed to the microsecond order. This makes it possible to obtain almost the same performance as when a PCIe switch is used. Since data transfer is performed on the Ethernet by using simple memory transfer (DMA), performance significantly exceeds that available from a system (iSCSI for example) that uses TCP/IP, which requires complex transaction-layer-protocol processing. Fig. 4 shows performance measurement results of random read for high-speed PCI-SSD. “Direct Insertion” Fig. 3 OS view of PCIe resources connected by ExpEther. Fig. 4 Performance comparison between ExpEther and various systems. Fig. 5 Automatic formation of PCIe trees by setting group ID. means that the device is directly inserted in the PCIe slot in the PC’s motherboard. Performance degradation in the ExpEther connection for random read access in the 4K size, for example, is insignificant as shown in Fig. 4. Another advantage of ExpEther is that the computer system configuration can be changed via management software by setting the group ID to the ExpEther chip remotely. This means PCIe logical connections can automatically be formed among the resources connected to ExpEther chips with the same group ID (Fig. 5). In other words, as long as resources have been connected to the ExpEther network in advance, hardware configurations can be modified by the resource management software described in the next section without physically inserting devices into or removing them from PCIe slots. 4. RD-PF Technology: Management Software Resource management software requires orchestration functionality that is, the ability to dynamically allocate resource on a device basis as necessary to meet the performance requirements of service applications and also maintain high reliability/availability. Orchestration software in data centers must be standards-compliant because this assures a consistent uniform management interface not only for RD-PF but for all the other resource disaggregated systems. To ensure standards compliance, the resource management software implemented in the RD-PF is based on OpenStack, which is the de facto standard in open source cloud management software. OpenStack is modularized according to function. The resource manstandard PCIe Switch Ethernet is transparent. Random Read IOPS ExpEther Host Host Host Host