User`s guide

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Adaptec Storage Management Software User’s Guide
I/O statistics are displayed in the Hard Drive I/O Statistics
window, as shown in Figure 3-17.
Figure 3-17 Hard Drive I/O Statistics Window
The Hard Drive I/O Statistics window displays the following
information:
I/O
Commands
The number of Read and Write commands issued by
the computer to the controller. If you use RAID and
caching, the number of commands issued to the
drives can differ significantly from this value.
Total Sectors The total number of sectors read and written from
the host computer.
Cache Hits The total number of sectors (read or written from
the host computer) that were found in the controller
cache and did not require a disk access.
Cache Misses The total number of sectors that were not accessed
from the controller cache, thus were read directly
from the disk.
Read-Ahead
Hits
The number of the cache hits for data read requests
satisfied by data held in the cache from previous
disk read-ahead operations.
Combined RAID SW-UG.book Page 48 Monday, September 9, 2002 1:25 PM