Software Architecture

The high-performance cloud disk optimization is based on the SPDK+Ceph solution. It runs the vhost service of the SPDK on a host to mount and manage Ceph cloud disks. Then, it passes cloud disks to VMs through the Vhost-user protocol to provide high-performance cloud disk storage. Figure High-performance cloud disk optimization software architecture shows the overall software architecture.

• The SPDK layer receives I/Os delivered by VMs and invokes the librbd interface of the Ceph client to forward the I/Os to the Ceph RADOS Block Device (RBD). Through CPU polling, the SPDK layer achieves higher performance than QEMU that directly invokes the Ceph librbd interface.
• At the Ceph client layer, the librbd interface is invoked by the SPDK to deliver Ceph RBD I/O requests. The Ceph client uses a series of algorithms to send I/O requests to the Ceph server over the network.

Figure 1 High-performance cloud disk optimization software architecture