Seagate ST336854FC Manual Do Utilizador

Página de 98
Cheetah 15K.4 FC Product Manual, Rev. B
15
want to configure the cache to provide large volumes of sequential data in a non-repetitive manner. In this 
case, the ability of the cache to “look ahead” to the next contiguous segments of sequential data is a good 
thing.
The Performance Mode (PM) bit controls the way the drive switches the cache buffer into different modes of 
segmentation. In “server mode” (PM bit = 0), the drive can dynamically change the number of cache buffer 
segments as needed to optimize the performance, based on the command stream from the host. In “desktop 
mode” (PM bit = 1), the number of segments is maintained at the value defined in Mode Page 8, Byte 13, at all 
times. For additional information about the PM bit, refer to the Unit Attention Parameters page (00h) of the 
Mode Sense command (1Ah) in the Fibre Channel Interface Product Manual, part number 77767496.