UMMMMMMMM......do you mean

Verifying that other resources as memory, CPU or network activities are not the real cause of the I/O

performance degradation.

• Controlling service levels as transactions per second, disk busy and disk response times (not provided by

most UNIX platforms) help in locating I/O performance problems.

• Modifying operating system parameters to improve read and write ahead activity, page stealing policy,

I/O pacing and logical volume implementation as striping, partition sizing , mirroring and data

positioning have major effects on I/O performance.

• Understanding how the application is accessing data (sequential or random access, reads vs writes) and

the block size is essential in order to choose the correct raid..