Installing Mylex Disk Array Controller Tape Drivers

Tune the following parameters:

SDSKOUT – Set this value to a number equal to 126 divided by the number of system drives being used. If required, round down the result to the next lower value so that its multiple does not exceed 126.

NMPBUF – Set this parameter for controller driver version 4.x or above.

Use the sar -hcommand to find the Scatter/Gather Buffer utilization and the Out of scatter/Gather buffers condition to set the buffer parameters.

Since the system configuration and the test suites differ significantly, the best way to tune either of these parameters is to evaluate the system activity report data. Refer to the SCO UNIX documentation for more information on methods and procedures that relate to acquiring and interpreting sar data.

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PCI Disk Array Controller Drivers Manual