NEC Storage Performance Monitor/Optimizer User manual

NEC Storage
Performance Monitor/Optimizer
User’s Manual

© NEC Corporation 2001-2003
No part of the contents of this book may be reproduced or
transmitted in any form without permission of NEC Corporation.
The contents of this book may be modified without notice in the future.

Preface
This manual describes NEC Storage PerformanceMonitor (performance monitoring function) and NEC Storage
PerformanceOptimizer (performance optimization function).
The performance monitoring function is for monitoring the performance of the Disk Array Subsystem (hereinafter may be
referred to as disk array), collecting performance information, and displaying the performance in real-time.
The performance optimization function is for optimizing the performance of the disk array by moving a logical disk in the
disk array, displaying the Busy Ratio, and estimating the Busy Ratio after it has been moved.
Refer to the “NEC Storage Manager Manual Guide” (IS901) for the overview of NEC Storage Manager and the related
manuals.
Remarks 1. This manual explains functions implemented by the following program products:
•NEC Storage Manager and NEC Storage BaseProduct
•NEC Storage PerformanceMonitor
•NEC Storage PerformanceOptimizer
2. This manual is applicable to the program products of the following versions:
•NEC Storage Manager Ver2.1
•NEC Storage BaseProduct Ver2.1
3. The term “iSM” in this text refers to all the NEC Storage Manager program products.
4. Trademarks and registered trademarks
•HP-UX is a registered trademark of Hewlett-Packard Co. in the United States.
•UNIX is a registered trademark of The Open Group in the United States and other countries.
•Microsoft®, Windows®, and Windows NT® are registered trademarks or trademarks of Microsoft
Corporation in the United States and other countries.
•Solaris is a registered trademark of Sun Microsystems, Inc. in the United States.
•Linux is a trademark or registered trademark of Mr. Linus Torvalds in the United States and other
countries.
Other product names and company names, etc. are registered trademarks or trademarks of the associated
companies.

6. In this document, matters to which careful attention needs to be paid will be described as follows:
Be sure to observe the contents.
If the indications are ignored and the system is improperly operated, settings which have been already made
might be affected.
Type of Indication
Type Description
Describes contents which require special attention during operation.
The First Edition in May 2002
The Third Edition in April 2003

i
Contents
Part I Performance Monitoring Function ..........................................................................................................I-1
Chapter 1 Overview of Performance Monitoring Function......................................................................................... I-2
1.1 Performance Monitoring Function............................................................................................................................I-2
1.2 NEC Storage PerformanceMonitor and Related Product .........................................................................................I-3
1.3 System Configuration ...............................................................................................................................................I-3
1.4 Operation of Performance Monitoring Function ......................................................................................................I-3
1.5 Function Overview....................................................................................................................................................I-5
Chapter 2 Installation of Performance Monitoring Function.................................................................................... I-25
2.1 Server Installation...................................................................................................................................................I-25
2.2 Client Installation....................................................................................................................................................I-26
Chapter 3 Operations of Performance Monitoring Function .................................................................................... I-27
3.1 Real-Time Display of Load Status..........................................................................................................................I-27
3.2 Monitoring Overloads.............................................................................................................................................I-41
3.3 Support for Analysis of Statistic Information.........................................................................................................I-50
Part II Performance Optimization Function.....................................................................................................II-1
Chapter 4 Overview of Performance Optimization Function.....................................................................................II-2
4.1 Performance Optimization Function....................................................................................................................... II-2
4.2 NEC Storage PerformanceOptimizer and Related Product .................................................................................... II-3
4.3 System Configuration ............................................................................................................................................. II-3
4.4 Operation of Performance Optimization Function ................................................................................................. II-4
4.5 Function Overview.................................................................................................................................................. II-5
Chapter 5 Installation of Performance Optimization Function..................................................................................II-7
5.1 Server Installation................................................................................................................................................... II-7
5.2 Client Installation.................................................................................................................................................... II-8
5.3 Installation of Work Disks for Optimization .......................................................................................................... II-9
Chapter 6 Operation of Performance Optimization Function (GUI) ......................................................................II-11
6.1 Description of Screen............................................................................................................................................ II-11
6.2 Operation on Screen.............................................................................................................................................. II-19
Chapter 7 Operation of Performance Optimization Function (CLI).......................................................................II-45
7.1 Logical Disk Movement Command...................................................................................................................... II-45
Appendix A Commands of Performance Monitoring/Optimization Function.................................................................1
A.1 Commands for Statistic Information File ................................................................................................................... 1
A.2 Command for Performance Tuning .......................................................................................................................... 17
Appendix B CSV File Structure.......................................................................................................................................... 20
Appendix C Report Format of Performance Report Editor ............................................................................................36
Appendix D Estimation of NEC Storage PerformanceMonitor File Size ....................................................................... 46
Appendix E Estimating Size of NEC Storage PerformanceOptimizer Files...................................................................48

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Appendix F Example of Performance Improvement........................................................................................................49
Index ...........................................................................................................................................................................51

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Chapter 1 Overview of Performance Monitoring Function
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Chapter 1 Overview of Performance Monitoring
Function
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The Performance Monitoring Function provides a performance monitoring function for centrally controlling the storage
performance under the control of NEC Storage Manager (hereafter, referred to as iSM). The use of this performance
monitoring function is capable of real-time monitoring of loads, detection of overload, and management of statistic
information (performance information of the past). The function allows an administrator to investigate the cause of access
performance deterioration, detect abrupt increases of accesses, and take proper measures against symptoms of failures (Note
1) on the business server.
Thus, this function enables constantly stable operation of storage devices.
Figure 1-1 Configuration of the Performance Monitoring Function
(Note 1)
The Performance Optimization function (NEC Storage PerformanceOptimizer) allows easy operation. Refer to Part II
“Performance Optimization Function” for details.
N
EC Storage Series
N
EC Storage
Performance Monitor
Operations
Administrator
ARRAY1 ARRAY2
ARRAY1
ARRAY2
LAN
Business Server
Performance
Monitoring Screen

Chapter 1 Overview of Performance Monitoring Function
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NEC Storage PerformanceMonitor requires the following program product as a precondition.
• NEC Storage BaseProduct
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Refer to Chapter 3 “System Configuration of NEC Storage Manager” of the “NEC Storage Manager Manual Guide”.
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This section describes operations of the Performance Monitoring Function. The Performance Monitoring Function is
operated in the flows shown below:
Operation flow Reference
Installing Performance Monitoring Function
Installation of the Performance Monitoring Function is accompanied by
installing NEC Storage Manager at the same time.
Chapter 2 Installation of Performance
Monitoring Function
Specifying targets of monitoring performances
For defining the targets of monitoring performances, specify disk array,
ports, logical disks, and physical disks composing logical disks used in
operations requiring responsibility such as online processing. Also,
specify monitoring items among those allowed for real-time monitoring
(I/O Density, transfer rate, etc.). For example, to monitor responses to
accesses from an application, average response time and I/O density
must be monitored.
1.5.1 Real-Time Display of Load State
3.1 Real-Time Display of Load State
Analyzing performances
Accumulate the statistic information of performance monitoring target
devices, with accesses from business programs. Then analyze the
statistic information by summarizing, extracting, and editing. On the
basis of the analyzed information, a maximum load level, load
fluctuation, and expected period of heavy load and future load
regulation are estimated. This analysis is performed regularly. If a
problem about performances is expected, an appropriate measure must
be taken in advance.
1.5.3 Analysis support for statistic
information
3.3 Support for Analysis of Statistic
Information
A.1 Commands for Statistic
Information File
Specifying threshold value and monitoring overloads
On the basis of performance analysis results, specify threshold values
as indexes for detecting overloads. Loads exceeding a specified
threshold value are detected by NEC Storage Manager automatically,
and are reported on the NEC Storage Manager Client screen.
1.5.2 Monitoring Overloads
3.2 Monitoring Overloads
Continued to next page
Operation flow Reference
continued from previous page
Upon detection of overload

Chapter 1 Overview of Performance Monitoring Function
I-4
Reviewing cause of overload
Display performance information on the real-time basis and check
location of overload. Then, analyze the accumulated statistic
information to determine the cause of the overload.
Displaying statistic information on a
real-time basis
1.5.1 Real-Time Display of Load State
3.1 Real-Time Display of Load State
Analyzing statistic information
1.5.3 Analysis support for statistic
information
3.3 Support for Analysis of
Statistic Information
A.1 Commands for Statistic
Information File
Improving performance
Analysis of statistic information makes it possible to improve
performance as shown in the examples provided below.
• If there is a problem with the file arrangement and the access load
concentrates in a specific logical disk, the I/O density of the logical
disk should be higher than that of other logical disks and its response
time should be longer. If this is the case, it is necessary to review
the file arrangement and distribute the load.
• If a write operation onto the disk is slow, the cache size is
insufficient. A write operation onto physical disks may be
simultaneously performed. This status is confirmed by checking to
see if the Write Hit ratio is less than 100%. If this is the case, it is
recommended that the cache size of the disk array be expanded.
• If response is not quick although the access density from the business
server to the logical disk is low, the access density to another logical
disk on the same RANK may be high. This state is confirmed by
the fact that the Busy Ratio of the RANK is high. If this is the case,
use the performance optimization function described in Part II to
move the logical disk, which has the high access density, to another
RANK and level out the Busy Ratio of each RANK. On the other
hand, reviewing the processes of a business application to reduce
access operations to a disk or improving access efficiency by batch
accessing can be good solutions to some cases.
Against high busy ratio on RANK:
Part II Performance Optimization
Function

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The Performance Monitoring function includes Real-Time Display of Load Status, Monitoring Overloads, and Statistic
Information Analysis Supporting.
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This function is capable of displaying the latest load state and usage of the disk array and disk array components. The
information is displayed upon the iSM client screen, on the real-time basis. The function, which can monitor
performances of multiple disk array, allows centralized monitoring on the same view of one iSM client. When storage
performance decreases, or symptom of a trouble is seen, use this function to display the performance information of disk
array and disk array components, and identify the cause of decreased performances or a fault.
For details of components composing disk array, refer to 3.3 “Hardware” in the “NEC Storage Manager Manual Guide”.
The iSM client screen is capable of displaying the index values for each calculation unit shown in Table 1-1. (Index values
applicable to the items indicated by “ √” in Table 1-1 are displayed.)
Table 1-1 Available Combinations of Monitored Items and Component types
Component type
Disk Array Port Logical Disk Physical Disk
External I/O Density √√√-
External Transfer Rate √√√-
External Average Transfer Length √√√-
External Average Response Time √√√-
Busy Ratio - - - √
Read Hit Ratio √- √-
Write Hit Ratio √- √-
Internal I/O Density - - - √
Internal Transfer Rate - - - √
Internal Average Transfer Length - - - √
Monitored Item
Internal Average Response Time - - - √
√: Item displayed -: Item not displayed
•Displays the latest load status in numerical values
Figure 1-2 Displaying the Numeric Table

Chapter 1 Overview of Performance Monitoring Function
I-6
•Displays the latest load state in bar graphs
Figure 1-3 Displaying the Bar Graph

Chapter 1 Overview of Performance Monitoring Function
I-7
•Displays the latest load state in time-series graphs
Figure 1-4 Displaying the Time-series Graph

Chapter 1 Overview of Performance Monitoring Function
I-8
(1) Monitored Items
Monitored items are types of index values which indicate status of load or performance. iSM displays values of the
following types of monitored items on the client screen.
(i) External I/O Density
This is the number of input/output requests received by the disk array from the external per unit time. The unit is
IOPS (Input Output Per Second). This is calculated by measuring the external I/O count during the unit
measurement period and dividing it by the time interval of the measurement period.
(ii) External Transfer Rate
This is the Average Transfer Rate of the input/output process achieved in response to the input/output requests
received by the disk array from the external. The unit is megabyte/second. This is calculated by measuring the
total of the amount of external data transfer during the unit measurement period and dividing it by the time interval of
the measurement period.
(iii) External Average Transfer Length
This is the average input/output data length per one input/output request received by the disk array from the external.
The unit is kilobyte. This is calculated by measuring the total of the amount of external data transfer and external I/O
count during the unit measurement period and dividing the former by the latter.
(iv) External Average Response Time
This is the Average Response Time for the input/output requests received by the disk array from the external. The
unit is millisecond. This is calculated by measuring the total of the external response time and external I/O count
during the unit measurement period and dividing the former by the latter.
(v) Busy Ratio
It is the ratio of operation of physical disk. The unit is percentage [%]. It is calculated by following expression;
dividing the operating time of physical disk by the time slot of measured segments.
(vi) Read Hit Ratio
It is the ratio of case where the READ request has been completed using data stored in the cache without reading from
physical disk (Read hit), when the disk array receives the input requests from outside. The unit is percentage [%]. It
is calculated by following expression; dividing the number of cache hit I/Os by the number of receiving READ
requests during the measuring interval.
(vii) Write Hit Ratio
This is the ratio of case where the WRITE request has been completed quickly by writing data only in the cache
(Write hit), when the disk array receives the output requests from outside. The unit is percentage [%]. It is calculated
by following expression; dividing the number of cache hit I/Os by the number of receiving WRITE requests during the
measuring interval.
(viii) Internal I/O Density
This is the number of input/output requests issued to the internal disk devices by the control device of the disk array.
The unit is IOPS (Input Output Per Second). This is calculated by measuring the internal I/O count during the unit
measurement period and dividing it by the time interval of the measurement period.
(ix) Internal Transfer Rate
This is the average transfer rate of the input/output requests issued to the internal disk devices by the control device of
the disk array. The unit is megabyte/second. This is calculated by measuring the total of the amount of internal

Chapter 1 Overview of Performance Monitoring Function
I-9
data transfer during the unit measurement period and dividing it by the time interval of the measurement period.
(x) Internal Average Transfer Length
This is the average input/output data length of the input/output process performed for the internal disk devices by the
control device of the disk array. The unit is kilobyte. This is calculated by measuring the total of the amount of
internal data transfer and internal I/O count during the unit measurement period and dividing the former by the latter.
(xi) Internal Average Response Time
This is the average response time for the input/output requests issued to the internal disk devices by the control device
of the disk array. The unit is millisecond. This is calculated by measuring the total of the internal response time
and internal I/O count during the unit measurement period and dividing the former by the latter.
(2) Unit to sum up
iSM separately displays values of the monitored items collected in the following units.
(i) Disk array
Statistic information of the entire disk array to be monitored is collected and load status for each disk array is reported.
For this component type, the external I/O Density, external Transfer Rate, external Average Transfer Length, external
Average Response Time, Read Hit Ratio, and Write Hit Ratio can be reported as monitored items.
(ii) Port
For the monitored disk arrays, statistic information related to each host port is collected separately, and load status for
each host port is reported. For this component type, the external I/O Density, external Transfer Rate, external
Average Transfer Length, and external Average Response Time can be reported as monitored items.
In principle, the sum of the values of a monitored item over all the host ports in one disk array is equal to the sum of
the values of the same monitored item over all the disk arrays. However, in a real-world situation, some error may
exist due to varied sampling time of the statistic information which is the basis of the values of the monitored item.
(iii) Logical disk
For the monitored disk arrays, statistic information related to each logical disk is collected separately, and load status
for each logical disk is reported. For this component type, the external I/O Density, external Transfer Rate, external
Average Transfer Length, external Average Response Time, Read Hit Ratio and Write Hit Ratio can be reported as
monitored items.
In principle, the sum of the values of a monitored item over all the logical disks in one disk array is equal to the sum
of the values of the same monitored item over all the disk arrays. However, in a real-world situation, some error may
exist due to varied sampling time of the statistic information which is the basis of the values of the monitored item.
(iv) Physical disk
Disk devices installed in a disk array are called physical disks. Statistic information related to each physical disk
installed in the monitored disk arrays is collected separately, and load status for each physical disk is reported. For
this component type, the internal I/O Density, internal Transfer Rate, internal Average Transfer Length, internal
Average Response Time, and Busy Ratio can be reported as monitored items.
You can set the update frequency (Display Refresh Rate) of display on the Numeric Table and the Time-series Graph by
using the environment setting at system installation.
You can change the setting from the iSM server menu while the iSM server is operating if the performance monitoring

Chapter 1 Overview of Performance Monitoring Function
I-10
screen is not started. For details of environment setting, refer to 2.1.3 “Environment Setting”.
The Display Refresh Rate determines the resolution of performance monitoring in the direction of time. Specify the
Display Refresh Rate in the number of updates per minute. Table 1-2 shows relation between Display Refresh Rate and
Display Refresh Interval.
Table 1-2 Display Refresh Rate and Display Refresh Interval.
Display refresh rate (times/minute) 1 2 3 4 5 6
Display refresh interval (second) 60 30 20 15 12 10
You cannot change the Display Refresh Rate while the Performance Monitoring screen is started. Change to the Display
Refresh Rate applies to all the disk arrays monitored by the server.
Increasing the Display Refresh Rate detects change in the performance information in a shorter interval but the number of
components simultaneously display is decreased. This is because the number of collection of performance information by
a single disk array unit in certain period is restricted not to obstruct file I/O from the application host in the overhead at
collection of performance information. This tendency is eminent especially when statistic information is being stored
simultaneously with real-time displaying.
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Specifying a threshold as an index value of overload allows iSM to automatically detect occurrence of overload in a disk
array or a disk array component (occurrence of a load exceeding specified threshold value). Upon detecting an overload, a
message notifying overload is displayed. At the same time, asterisks (**) are displayed on the location of the Performance
Monitor screen. When occurrence of an overload is reported by a message, an administrator must identify location of the
overload on the Performance Monitor screen.
N
EC Storage Series
N
EC Storage
PerformanceMonitor
Operations
Administrator
ARRAY1 ARRAY2
ARRAY1
…
…
…
…
…
ARRAY2
…
…
…
**
LAN
Business Serve
r
Performance
Monitoring Screen
Overload
Occurrence
Display
Overload

Chapter 1 Overview of Performance Monitoring Function
I-11
Figure 1-5 Monitoring Overloads
A threshold value is specifiable for each calculation unit displayed by the Real-Time Display function (refer to Table
1-1). The unit of specifying a threshold is called a threshold monitoring element. Thresholds can be specified by
clients with the user level (Note 1) L2 or L3.
(Note 1)
For user levels, refer to 5.2 “Client Start/Stop” of the “NEC Storage Manager User’s Manual” of your OS.
(1) Notifying threshold excess by e-mail
You can also e-mail the message notifying you of occurrence of an exceeded threshold to a specified address by using
the link function of the iSM server. For details of the link function of the iSM server, refer to 3.6 “Event Link” in the
“NEC Storage Manager User’s Manual” of your OS.
(2) Threshold monitoring conditions
During a background process of disk array, such as batch processing and fault recovery of physical disks, a threshold
value may be temporarily exceeded. Upon such a case, which can occur in usual operation in general, exceeding of
threshold should not be reported to an administrator. Specifying the monitoring conditions shown below can prevent
such unnecessary reporting of exceeded threshold.
1. Threshold monitoring interval
Time interval of judging threshold. Default value is the same as Display Refresh Interval.
2. Minimum I/O count
If the number of I/Os in a threshold monitoring interval does not exceed an I/O count specified here, the threshold
is not monitored in this interval. A minimum I/O count is specified with the number of I/Os per minute.
Default value is 60/minute.
A threshold is monitored if the number of I/Os in a threshold monitoring interval exceeds the minimum I/O count, and
if the threshold is exceeded, threshold exceeding is reported. By operating businesses, analyzing performances, and
specifying the threshold monitoring conditions on the basis of the analysis, monitoring of overload appropriate for the
businesses. Figure 1-6 shows an outline of the threshold monitoring interval.

Chapter 1 Overview of Performance Monitoring Function
I-12
入出力回数
しきい値監視インターバル（目盛りの単位：1 分）
しきい値
しきい値監視インターバルを
1 分と設定した場合
しきい値監視インターバルを
5分と設定した場合
しきい値監視インターバルが短いため、一時的な
過負荷でしきい値超えが通知される
Figure 1-6 Threshold Monitoring Interval
(3) Resetting threshold excess state
Once a threshold value is exceeded, the value is excluded from threshold monitoring target until the threshold excess
occurrence state is reset. This feature prevents repeated reporting of the same event of threshold excess state, under
largely fluctuating loads.
The threshold excess state is cancelled by operations on the Performance monitoring screen. Specifying the
conditions for resetting threshold excess state allows reset of threshold excess state when the conditions are satisfied.
The following conditions are specifiable for resetting the threshold excess state:
1. Time of continued values under threshold
Specify the number of threshold monitoring intervals during which a value is kept under threshold. For each
monitoring item satisfying the conditions, threshold excess state is reset. If the number of I/Os does not reach a
minimum number of I/Os specified by threshold monitoring conditions, the load of applicable interval is
recognized as under threshold.
2. Time of day
At a specified time of each day, the threshold excess state is reset for all monitoring items.
Figure 1-7 shows an example of resetting threshold excess state when “3” is specified as the number of threshold
monitoring intervals for a period of continuous values under threshold.
value of
monitored
item
Because of short threshold monitoring interval, exceeded
threshold is notified upon a temporary overload.
Threshold monitoring interval (scale: 1 minute)
Threshold value
Specifying “1 minute” for a
threshold monitoring interval
Specifying “5 minutes” for a
threshold monitoring interval

Chapter 1 Overview of Performance Monitoring Function
I-13
しきい値監視インターバル
しきい 値 超 え 検 出
しきい 値 超 え 検 出しきい 値 超 え 検 出
しきい 値 超 え 検 出
しきい値超え状態
しきい値超え状態しきい値超え状態
しきい値超え状態
しきい値監視インターバル（３回）
しきい
値
監
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値
監
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インターバル（３回）
しきい値監視インターバル（３回）
しきい値超えの通知 しきい値超えの通知 しきい値超えの通知
iSMクライア ント
Figure 1-7 Resetting Threshold Excess State
Threshold monitoring
interval
Detect threshold
exceedin
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N
otify threshold
excess
N
otify threshold
excess
iSM Client
Threshold excess state
Threshold monitoring
intervals (3 times)

Chapter 1 Overview of Performance Monitoring Function
I-14
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This function is capable of to accumulating, concentrating, and editing statistic information about the performances of disk
array in a file. Using this function allows long-term accumulation of statistic information which lets you grasp long-term
load variations and analysis of performance, for efficient use of the disk array.
A file where statistic information is accumulated is called a statistic information history file. The statistic information
history file is stored on the iSM management server, allowing concentrating, extracting, and editing data on the server. In
addition, downloading the statistic information history file allows concentrating, extracting, and editing data on an iSM
client.
NEC Storage
PerformanceMonitor
Figure 1-8 Analyzing Statistic Information
Statistic information
history file
1. Accumulating statistic information
2. Concentrating, extracting, and editing statistic
information
NEC
Storage
iSM Client
O
r
2. Downloading
accumulated statistic
information
3. Concentrating,
extracting, and editing
statistic information