Use Direct I/O (-directio) to open all files in unbuffered mode, which enables the OpenEdge RDBMS to use an I/O technique that bypasses the operating system buffer pool and transfers data directly from a buffer to disk. This technique avoids the overhead of maintaining the operating system buffer pool and eliminates competition for operating system buffers between OpenEdge programs and other programs.

You might improve performance by using the direct I/O feature. To use direct I/O, use Blocks in Database Buffers (-B) to increase the size of the buffer pool, since OpenEdge database I/O will not pass through the operating system buffer pool. Also, decrease the size of the operating system buffer pool to compensate for the additional memory allocated to the database.