HP StorageWorks Command View SDM Installation and User Guide (T1086-96023, February 2005)

Command Line User Interface 171
Command Line User Interface
RAID 1+0 to RAID 5 DP
Relocations Spawned by
MakeSpace
OPAQUE The number of clusters that were relocated by the make
space policy from RAID 1+0 to RAID 5 DP storage.
Usage
RAID 5 DP provides better storage efficiency than RAID
1+0. If more free space cannot be obtained by garbage
collecting holes in RAID 5 DP storage areas (reference the
“RAID 5 DP to RAID 5 DP Relocations Spawned by
MakeSpace” metric) and there are no holes available to
post write cache data in RAID 1+0 storage areas
(reference the “RAID 1+0 to RAID 1+0 Relocations
Spawned by MakeSpace” metric) and there is no
unallocated free space available, then the make space
policy will move data from RAID 1+0 to RAID 5 DP to
make more free space. Unlike the optimize policy, the
make space policy does not discriminate by the recency of
writing when selecting data to be relocated from RAID
1+0 to RAID 5 DP. Since the make space policy only runs
when host writes are waiting to be completed, there is no
time available to locate the least recently written data.
RAID 1+0 to RAID 1+0
Relocations Spawned by
Optimize
OPAQUE The number of clusters that were relocated by the optimize
policy from RAID 1+0 to RAID 1+0 storage.
Usage
The RAID 1+0 storage areas can become filled with holes
of empty space that need to be garbage collected to make
the space available as free space. These relocations are
used to do garbage collection in the RAID 1+0 storage
areas.
RAID 1+0 to RAID 5 DP
Relocations Spawned by
Optimize
OPAQUE The number of clusters that were relocated by the optimize
policy from RAID 1+0 to RAID 5 DP storage.
Usage
Optimize uses these relocations to move the least recently
written data to RAID 5 DP storage so there is space
available in RAID 1+0 storage for the write working set
(reference the RAID 5 DP to RAID 1+0 DP Relocations
Spawned by Optimize metric).
Table 12 Performance Metrics (Continued)
Metric Categories Description/Usage