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

162 Command Line User Interface
New RAID 5 DP Writes OPAQUE The number of write operations to RAID 5 DP storage that
caused allocation of new space in RAID 5 DP.
Usage
New writes are host writes to LUN addresses that have not
been written since the LUN was created. Rewrites are host
writes to LUN addresses that have already been written at
least once since the LUN was created. AutoRAID will
decide whether to place write data into RAID 1+0 or RAID
5 DP storage when it is posted out of the write cache.
Relocations are movements of data currently stored in the
array from one location to another. All of these types of
write operations can cause allocation of new space in
RAID 5 DP storage and so are counted by this metric. A
large number of these allocating writes such as may occur
when loading data onto a newly created LUN or when a
rebuild operation is taking place can cause free disk space
to be consumed rapidly leading to possible invocation of
the make space policy and the associated performance
impacts. AutoRAID attempts to detect the data load
scenario and direct new writes to RAID 5 DP storage so as
to conserve free disk space in that case.
Table 12 Performance Metrics (Continued)
Metric Categories Description/Usage