Справочник Пользователя для DELL 34XX

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hit blocks, it is possible that a different I/O characteristic type (file system, database, 
or web server) could improve the performance.
Misses
Number of host reads where none of the blocks were in the SSD cache. This is an 
SSD cache miss where the reads were satisfied from the base virtual disk.
Misses - Blocks
Number of blocks in Misses.
Populate 
Actions (Host 
Reads)
Number of host reads where data was copied from the base virtual.
Populate 
Actions (Host 
Reads) - Blocks
Number of blocks in Populate Actions (Host Reads).
Populate 
Actions (Host 
Writes)
Number of host writes where data was copied from the base virtual disk to the SSD 
cache.
The Populate Actions (Host Writes) count may be zero for the cache configuration 
settings that do not fill the cache as a result of a Write I/O operation.
Populate 
Actions (Host 
Writes) - Blocks
Number of blocks in Populate Actions (Host Writes).
Invalidate 
Actions
Number of times data was invalidated/removed from the SSD cache. A cache 
invalidate operation is performed for every host write request, every host read 
request with Forced Unit Access (FUA), every verify request, and in some other 
circumstances.
Recycle 
Actions
Number of times that the SSD cache block has been reused for another base virtual 
disk and/or a different LBA range.
For effective cache operation, it is important that the number of recycles is small 
compared to the combined number of read and write operations. If the number of 
Recycle Actions is close to the combined number of Reads and Writes, then the 
SSD cache is thrashing. Either the cache capacity needs to be increased or the 
workload is not favorable for use with SSD cache.
Available Bytes
Number of bytes available in the SSD cache for use by this RAID controller module.
The available bytes, allocated bytes, and user data bytes are used to compute the 
Cache Allocation % and the Cache Utilization %.
Allocated Bytes
Number of bytes allocated from the SSD cache by this RAID controller module. 
Bytes allocated from the SSD cache may be empty or they may contain data from 
base virtual disks.
The available bytes, allocated bytes, and user data bytes are used to compute the 
Cache Allocation % and the Cache Utilization %.
User Data Bytes
Number of allocated bytes in the SSD cache that contain data from base virtual 
disks.
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