Auto lun/performance control base monitor, Auto lun xp statistics, 2 auto lun/performance control base monitor – HP StorageWorks XP Remote Web Console Software User Manual

Page 49: 2auto lun/performance control base monitor

Advertising
background image

Auto LUN XP user guide for the XP12000/XP10000

49

2

Auto LUN/Performance Control Base Monitor

Auto LUN XP statistics

Disk arrays automatically collect statistics twice a day (in the morning and afternoon). Auto LUN XP

monitors disk arrays and obtains usage statistics about resources such as front-end and back-end

processors, hard disk drives, and logical volumes every 15 minutes.
Auto LUN XP displays statistics collected for the last three months. Statistics over three months old are

discarded.
You can specify a time period and view a graph illustrating how usage rates change within that time

period. You can also view average and maximum usage rates.
You can analyze information displayed on the pane and identify overloaded resources. If necessary, take

load-balancing measures to improve system performance.
Auto LUN XP displays the following types of information:

Usage statistics about parity groups. If data shows overall high parity group usage, consider installing

additional HDDs and using Auto LUN XP to migrate high-usage volumes to the new parity groups. If

monitor data shows unbalanced parity group usage, use Auto LUN XP to migrate volumes from

high-usage parity groups to low-usage parity groups.

Usage statistics about logical volumes. Auto LUN XP displays average and maximum usage, including

sequential and random access, for each LDEV in a parity group. Logical volume usage is the time in

use (sequential and random access) of the physical drives of each LDEV, averaged by number of

physical drives in the parity group.
If data shows overall high logical volume usage, consider installing additional hardware (for example,

HDDs, DKAs, or cache). If monitor data shows unbalanced volume usage, use Auto LUN XP to migrate

high-usage volumes to higher HDD classes and/or lower-usage parity groups. You can also use logical

volume usage data to analyze access characteristics of volumes and determine appropriate RAID level

and/or HDD type for the volumes.

Usage statistics about channel adapters and channel processors. Channel adapters (CHAs) process

host commands and control data transfer between hosts and cache. A channel adapter contains

multiple channel processors (CHPs), which process host commands and control data transfer.
If data shows overall high CHA usage, consider installing additional CHAs. If data shows unbalanced

CHP usage, consider moving some devices defined on overloaded ports to ports with lower-usage

CHPs to balance front-end usage.

Usage statistics about disk adapters and disk processors. Disk adapters (DKAs) control data transfer

between cache and disk devices. A disk adapter contains multiple disk processors (DKPs), which

control data transfer.
If data shows overall high DKP usage, consider installing additional HDDs and/or DKAs and using

Auto LUN XP to migrate high-write-usage volumes (especially sequential writes) to the new parity

groups. If data shows unbalanced DKP usage, use Auto LUN XP to migrate logical volumes from

high-usage parity groups to low-usage parity groups.
Auto LUN XP cannot estimate DKP usage. Use Auto LUN XP migration only for obvious cases of high or

unbalanced DKP usage. Auto LUN XP migration might not improve performance if DKP usage values

vary only slightly or if overall DRR usage values are relatively high.

Usage statistics about data recovery and reconstruction processors. Data recovery and reconstruction

processors (DRRs) are microprocessors located on DKAs that generate parity data for RAID-5 parity

groups. DRRs use “old data + new data + old parity” to generate new parity.
If data shows overall high DRR usage, this might indicate a high write penalty. Consult your

HP representative about high write penalty conditions. If data shows unbalanced DRR usage, consider

using Auto LUN XP to relocate volumes to balance DRR usage within the disk array.

Write pending rate. The write pending rate indicates the ratio of write-pending data to cache memory

capacity. The Auto LUN pane displays average and maximum write pending rates for the specified time

Advertising
This manual is related to the following products: