Справочник Пользователя для DELL 32XX

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Parameter
Description
brackets ([ ]). If the SSD cache name contains 
special characters or consists only of numbers, you 
also must enclose the identifier in double 
quotation marks (" ") inside square brackets.
controller
Each RAID controller module stores SSD cache 
metadata for the virtual disks that it owns. 
Therefore, the SSD cache statistics are maintained 
and displayed per RAID controller module. Valid 
RAID controller module identifiers are 0, 1, or both, 
where 0 is the RAID controller module in slot 0, 1 
is the RAID controller module in slot 1, and both is 
both RAID controller modules. Enclose the RAID 
controller module identifier in square brackets ([ ]). 
If you do not specify a RAID controller module, the 
default value is both.
file
The file path and the file name to which you want 
to save the SSD cache statistics. Additional 
statistics are available when you save the statistics 
to a file.
Enclose the file name in double quotation marks (" 
"). For example: file="C:\Program Files\CLI\logs 
\statistics.csv".
Notes
The following statistics are displayed on the screen:
Reads
Total number of host reads of SSD cache-enabled virtual disks.
Compare the Reads relative to Writes. The Reads need to be greater than the 
Writes for effective SSD cache operation. The greater the ratio of Reads to Writes 
the better the operation of the cache.
Writes
Total number of host writes to SSD cache-enabled virtual disks.
Cache Hits
A count of the number of cache hits.
Cache Hits (%)
Derived from Cache Hits/total reads.
The Cache Hit percentage should be greater than 50% for effective SSD cache 
operation. A small number could be indicative of several things:
• Ratio of Reads to Writes is too small
• Reads are not repeated
• Cache capacity is too small
NOTE: To help determine the ideal SSD cache capacity, you can run the 
Performance Modeling Tool using the start ssdCache [ssdCacheName] 
performanceModeling command.
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