Fujitsu MBA3147NC User Manual

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 Notes: 
1.  The user can arbitrarily specify the following parameters according to the system 
requirements: 
• 
ARRE 
• 
AWRE 
• 
TB 
• 
PER 
2.  The user also can arbitrarily specify parameters other than the above.  However, it is 
recommended to use the default setting in normal operations. 
 
(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 SCSI bus 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 2 "Data Buffer Management" of the SCSI Logical Interface Specifications for 
further details. 
 
 
Parameter  
Default 
value 
• Buffer full ratio 
 
00 (HEX) 
• Buffer empty ratio 
 
00 (HEX) 
 
 Notes: 
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 data transfer rate of the SCSI bus 
• 
Average amount of processing data specified with a command 
Refer to Chapter 2 "Data Buffer Management" of the SCSI Logical 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. 
 
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