Optimizing disk performance in NT4

Optimizing disk performance in NT4
Hi Everyone,

I am trying to optimize read/write performance to disk drives. The disk
drive is the initiator of a DMA. The ATA-66 drives that I have tested work
best when the DMA size is around 512KB. The Raid drives that I have tested
work best when the DMA size is 2MB or above. Do these numbers(512KB and
2MB) coorespond to the amount of cache memory that is either on the disk
controller, on the disk itself, or a combination? If the numbers do
coorespond to the amount of cache memory is there a way for an NT4.0 driver
to determine this cache size? Is there a way to tell what size DMA chunck
to use for optimum performance?

Please reply to: xxxxx@iced.com
Marty Corbett
Integrated Computing Engines (ICE)

> drive is the initiator of a DMA. The ATA-66 drives that I have tested
work

best when the DMA size is around 512KB. The Raid drives that I have

Very strange. AFAIK ATAPI DMA controller is capable only of 16 pages
transfers - which is 64K.

Max