Communications storage manager (CSM) overview

This chapter describes CSM and its capabilities, and includes the following sections:

CSM application programming interface (API)
Installing, defining, and initializing CSM
Monitoring CSM storage
Diagnosing CSM problems
Application responsibilities for using CSM
Functions provided by the CSM API

The communications storage manager (CSM) is a VTAM® component that allows authorized host applications to share data with VTAM and other CSM users without the need to physically copy the data.

CSM is provided as part of the high performance data transfer (HPDT) family of services. HPDT optimizes system performance for the transfer of bulk data. By providing a means for authorized applications to share buffers, CSM improves system performance during the transfer of bulk data by reducing the processing required for data movement. As a result, the following central processing unit (CPU) resources are conserved:

CPU cycles
Memory bus
Cache