C141-E078-02EN 5 - 13
(2) Disconnection/reconnection parameters (page code = 2)
The following parameters are used to optimize the start timing of reconnection processing to
transfer data on the loop at a read (READ or READ EXTENDED command) or write operation
(WRITE, WRITE EXTENDED, or WRITE AND VERIFY command) of the disk. Refer to
Chapter 3 of Fibre Channel Interface Specifications for further details.
a. Disconnection/reconnection parameters (page code = 2)
Parameter Default value
• Buffer full ratio 20 (HEX)
• Buffer empty ratio 20 (HEX)
IMPORTANT
1. In a system without the disconnection function, these parameters
need not be specified.
2. Determine the parameter values in consideration of the
following performance factors of the system:
• Time required for reconnection processing
• Average amount of processing data specified with a
command
Refer to Chapter 3 of Fibre Channel Interface Specifications for
how to obtain the rough calculation values for the parameter
values to be set. It is recommended to evaluate the validity of
the specified values by measuring performance in an operation
status under the average system load requirements.
(3) Caching parameters
The following parameters are used to optimize IDD Read-Ahead caching operations under the
system environments. Refer to Chapter 3 of Fibre Channel Interface Specifications for further
details.
