AppLogic 云平台

The AppLogic Distributed Kernel provides a set of system services required to implement the distributed infrastructure and application model of AppLogic. The three most important system services include the Global Volume Store, the Distributed Virtual Machine Manager and the Logical Connection Manager. Together, these services abstract the distributed nature of the underlying grid, virtualize its hardware resources, and provide the runtime abstractions necessary to implement the rest of AppLogic.

 Global Volume Store (GVS)

GVS implements a new type of distributed storage subsystem that combines the advantages of a global file system with an object store. The key object supported by GVS is a virtual volume. Virtual volumes exist in a hierarchical namespace, can be created, destroyed and cloned on demand, and are mirrored on multiple servers for read performance and availability.

GVS scales linearly to hundreds of servers in both performance and capacity. Due to advanced caching and network access algorithms, GVS volumes are generally 10-15% faster than local physical disks. In addition, GVS supports the ability to take snapshots of a volume or a set of volumes, which makes it easy to backup entire applications.

 Distributed Virtual Machine Manager (DVM)

The AppLogic distributed virtual machine manager is built on top of the Xen hypervisor, the leading open source server virtualization technology. DVM extends Xen with grid-specific functionality and provides ability to create a virtual machine anywhere on the grid, guarantee hardware resource assignment for each VM and schedule sets of virtual machines across the grid.

 Logical Connection Manager (LCM)

The logical connection manager abstracts intercomponent communications. It enables AppLogic to define all interactions between components of an application in terms of point-to-point logical connections between virtual appliances. The interactions are controlled and tunneled across physical networks, allowing AppLogic to enforce interaction protocols, detect security breaches and migrate live TCP connections from one IP network to another transparently.