NCL VSAM Techniques › Obtain I/O Buffers

Obtain I/O Buffers

At the time the RPL is generated an I/O buffer is also obtained. This buffer is large enough to hold the largest record that could be read from, or written to, the UDB. Therefore, it is important to accurately define the record sizes when the VSAM cluster is allocated. Specification of record sizes in excess of that required not only impacts VSAM algorithms for space allocation, but also forces your product to obtain buffers of an unnecessary size, thus wasting storage.