CA-L-Serv › Define Managed Files › Buffer Pools

Buffer Pools

VSAM uses buffer pools to read and write records from the disk and to transfer records to and from a user-provided area in the client address space. Two types of buffer pools:

• Private buffer pools, which are reserved for a single file.

  By default, VSAM creates a private buffer pool when the data set is initially opened. Define private buffer pools to CA-L-Serv to override the VSAM defaults, which can be done by using the BUFNI, BUFND, and STRNO keywords of the ADDFILE command.

• Local shared resource (LSR) buffer pools, which are shared by a set of files you designate. Files that share a buffer pool have similar buffer characteristics. we recommend that you use LSR buffer pools for files with similar characteristics because this improves service times for most types of I/O processing.

  You can define up to 15 LSR buffer pools using the ADDPOOL command.

See the documentation for the client application for recommendations on which data sets are assigned to private (NSR) or shared pools (LSR).