Write Pending Rates; Usage Rates Of Access Paths - HPE XP7 User Manual

Storing period
Short-Range can be specified.
Selection of monitoring objects
Select the desired monitoring objects in the Performance Objects field.
Item on left side of Object
field
Cache

Write pending rates

Function
The write pending rate indicates the ratio of write pending data to the cache memory capacity.
It is expressed as a percentage of the cache memory capacity used for write pending. The Monitor
Performance window displays the average and the maximum write pending rate for the specified
period of time.
Storing period
Short-Range or Long-Range can be specified.
Selection of monitoring objects
Select the desired monitoring objects in the Performance Objects field.
Item on left side of Object
field
Cache

Usage rates of access paths

Function
The access paths are the paths through which data and commands are transferred within a
storage system. As shown in the following figure, the channel adapters (CHAs) (also called
channel adapters) in the XP7 Storage system control the transfer of data between the hosts and
the cache memory, and the disk adapters (DKAs) (also called disk adapters) control the transfer
of data between the cache memory and the data drives, as shown below. Data transfer does not
occur between the channel adapters and disk adapters. Data is transferred through the CM
package (cache switch) to the cache memory.
When hosts issue commands, the commands are transferred through the channel adapters to
the shared memory (SM). The content of the shared memory is checked by the disk adapters.
Performance Monitor tracks and displays the usage rate for the following access paths.
Access paths between channel adapters and the CM package (CHA cache)
Access paths between disk adapters and the CM package (DKA cache)
Access paths between the MP blade and the CM package (MP blade cache)
Access paths in the CM package (cache)
34 Performance Monitor data
Item on right side of
Object field
None
Item on right side of
Object field
None
Item on left side of
Monitor Data field
Usage Rate (%)
Item on left side of
Monitor Data field
Write Pending Rate (%)
Item on right side of
Monitor Data field
None
Item on right side of
Monitor Data field
None