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

160 Command Line User Interface
Make Space For Write
Invocations
OPAQUE The number of times the make space policy has been
invoked.
Usage
The make space policy runs only in foreground on
demand when free disk space is needed to post data from
the write cache so that space can be freed up in the write
cache to process host write commands. This can cause a
significant delay in processing of the host write commands
that are waiting. Even one invocation of the make space
policy can potentially cause a noticeable performance
degradation. As the array comes close to running out of
free disk space the optimize policy switches from its
normal mode into a priority mode to make free disk space
in an attempt to avoid invocation of the make space
policy. Each invocation of the make space policy is an
indication that data was migrated to make more free disk
space. An array that is experiencing a relatively high rate
of make space invocations will very likely be achieving
unacceptably low performance levels.
Maximum Operating Temperature DISK-PORTS The maximum reported sensor temperature in degrees
Celsius at which the drive will operate continuously
without degrading the drives operation or reliability
outside the limits specified by the manufacturer of the drive
Usage
The comparison of the Actual Temperature with the
Maximum Operating Temperature indicates how close the
drive is to its operational limits.
Table 12 Performance Metrics (Continued)
Metric Categories Description/Usage