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

Buffer Pools

VSAM uses buffer pools to read and write records from disk and to transfer records to and from a user provided area in the client address space. There are 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. You only need to define private buffer pools to CA-L-Serv if you wish 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 should have similar buffer characteristics. CA recommends that you use LSR buffer pools for files with similar characteristics because this will improve 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 should be assigned to private (NSR) or shared pools (LSR).