Справочник Пользователя для Promise Technology 66 Pro

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SuperTrak66™ User's Manual 
Chapter 5 
 
- 85 - 
 
System Cache Policy 
The “System cache policy” section contains a series of fields and text 
boxes as follows: 
 
 
 
Cache block size (KB) 
This field reflects the size of a unit block in the cache module. It 
cannot be modified from here. 
 
 
Total cache size (MB) 
This field indicates how much of the SuperTrak66 EDO memory is 
being used for R/W caching plus RAID XOR data space.  
 
NOTE: Not all installed memory is available. A portion of cache 
memory is used to house I
2
O and other components of the 
Promise driver.  
 
 
RW cache size (MB) 
This field indicates how much of the SuperTrak66 EDO memory is 
being used for R/W caching only. 
 
 
 
Flush frequency timer (sec) 
This field shows how long (in seconds) a block of “dirty” data can 
remain in memory without being flushed. This field affects the 
cache configurations of any array attached to this IOP. 
 
 
 
Dirty threshold flush start 
This field indicates the flush start threshold percentage of dirty 
blocks. When the percentage of dirty blocks residing in memory 
exceeds the threshold, flushing will begin automatically. This field 
affects the cache configurations of any array attached to this IOP. 
 
 
 
Dirty threshold flush stop 
This field shows the flush stop threshold percentage of dirty blocks. 
When the percentage of dirty blocks residing in memory falls 
below the threshold, flushing will stop automatically. This field 
affects the cache configurations of any array attached to this IOP. 
 
 
Commit / Reset 
If changes are made to any of the “System Cache Policy” fields, 
press the “Commit” button to save the new settings, or “Reset” 
to make the values revert to their saved settings.  
 
NOTE: The new settings will NOT be enabled until the next 
system boot.