Data Type

Integer

Default Value

8192 Integer words.

Description

This parameter determines the size of the buffer used for submatrix integer records.

When you call FMSOS to open a submatrix file, two buffers of size LBUFSI are created to store the submatrix integer data. As you call FMSWRT or FMSSWR to write the data to disk, it is first transferred to these buffers.

FMS delays opening a physical file until both buffers are full. That way if the two buffers are large enough to hold the entire file, no disk transfers are performed.

If the amount of data you write exceeds 2*LBUFSI, a physical file having a record length LBUFSI is opened. As you continue to write to the file, data is staged in one buffer while the other is written to disk asynchronously.

For today's large memory machines, it is usually possible to keep the submatrix files incore. You should try setting the INCORE option prior to calling FMSOS to create an incore submatrix file.