Tips For Configuring The Disk Array O Nhp-Ux - HP Surestore Disk Array 12h - And FC60 System Administrator Manual

Tips for Configuring the Disk Array On HP-UX
Before installing a new disk array, you should determine what is more important for your operating
environment — performance or capacity. This decision will influence how you configure the disk array
hardware and LVM. There are several configuration options that impact the performance of the disk array.
Table 2 identifies the various configuration options, their impact on disk array performance, and any
considerations regarding disk array capacity.
NOTE! Overall system performance is a complex issue influenced by many factors. The
configuration options described here will increase the potential performance of the disk array.
However, the actual performance of the disk array will be determined largely by host demand.
AutoRAID technology is particularly suited to I/O-intensive application environments such as
OLTP and NFS. It is in these environments that the performance benefits offered by AutoRAID
will be fully realized.
Configuration
Option
Number of LUNs
per disk array
Number of disk
arrays per SCSI
host adapter
Managing the HP SureStore E Disk Array 12H on HP-UX
Table 2. Configuration Options
Impact on Performance and Capacity
Performance. Increase the number of LUNs per disk array to improve
performance. More LUNs increases the size of the I/O command queue
allocated by HP-UX, which increases throughput. The recommended
number of LUNs is 4 to 6.
Capacity. To allow for future capacity expansion, avoid creating the
maximum number of LUNs (8) on the disk array. New capacity is made
available through the creation of a new LUN. If the maximum number of
LUNs have already been created, it will be necessary to delete and
recreate an existing LUN to increase capacity.
Performance. Limit the number of disk arrays per host adapter to
improve performance. The recommended configuration for maximum
performance is:
NIO adapter - 3 disk arrays
GSC adapter - 8 disk arrays
Capacity. If maximum capacity is more important than performance,
connect the maximum number of disk arrays to each adapter.
Tips for Configuring the Disk Array On HP-UX
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