These three programs work together to coordinate the recovery of protected
resources and the records within a recoverable VSAM data set:
- Application program
- The application program accesses protected resources and requests changes
to the resources.
- Resource manager
- A resource manager controls and manages access to a resource.
A resource manager is an authorized program that provides an application programming
interface (API) that enables the application program to read and change a
protected resource. The resource manager, in conjunction with the syncpoint
manager, controls whether changes to resources are committed or backed out.
For DFSMStvs, the resources consist of records in recoverable VSAM data sets.
- Syncpoint manager
- A syncpoint manager uses a two-phase commit protocol to coordinate
changes to protected resources, so that either all changes are made or none
of the changes are made. Recoverable resource services (RRS) functions as
the syncpoint manager.