SOS Global Summary
The Global Summary Screen
The sos Global Summary screen provides a summary of activity system-wide:
Product version and collection interval information
Key indicators of performance data
Global statistics
CPU utilization statistics
CPU miscellaneous statistics
Memory and virtual memory statistics
Miscellaneous statistics
Disk statistics
Process statistics
Workload statistics
System performance advice
The Global Summary screen is the first screen to display when you start sos and the usual
starting point for any review of system activity and performance. The screen can be displayed in
either graphical or tabular format.
To access the Global Summary screen from any sos display screen:
Type s from the sos Enter command: prompt to view the Screen Selection Menu screen.
From the Screen Selection Menu screen, enter g (Global Summary). The Global Summary screen will display.
Type t from the Global Summary screen to toggle between the graphical and tabular formats.
Graphical Format
Figure 9.1 shows an example of the Global Summary screen in graphical format.
Figure 9.1 SOS Global Summary screen (graphical format)
The graphical Global Summary screen can show the following information:
The SOS banner
The Key Indicators of Performance (KIP) line (optional)
GLOBAL statistics
PROCESS SUMMARY (optional)
WORKLOAD SUMMARY (optional)
SYSTEM PERFORMANCE ADVICE messages (optional)
Tabular Format
To toggle between the graphical and tabular format options, press the t key from the Global
Summary screen.
Figure 9.2 shows an example of the Global Summary screen in tabular format.
Figure 9.2 SOS Global Summary screen (tabular format)
The tabular Global Summary screen can show the following information:
The SOS banner
CPU UTILIZATION statistics (including cumulative statistics)
CPU MISC statistics
MEM/VM statistics (optional)
MISC global statistics (optional)
DISK statistics (optional)
PROCESS SUMMARY (optional)
SYSTEM PERFORMANCE ADVICE messages (optional)
Global Summary Screen Display Items
SOS Banner
The SOS banner is always displayed at the top of all SOS data display screens.
Figure 9.3 SOS Global Summary screen: SOS banner
The banner contains information about the SOS program, the host system, the elapsed interval,
and the current interval.
Product Version Number (SOS V.nnx)
The first item displayed in the SOS banner (reading left to right) is the product version number
(SOS V.nnx). The version number denotes the following about the product:
SOS is the name of the product.
V denotes the major version level.
nn denotes the minor version level.
x denotes the fix level.
The SOS version number displayed in the example (refer to
Figure 9.3) is B.01y. When contacting
technical support, please provide the product version number of the software installed on your
system.
System Name
The second item displayed in the SOS banner is the name of the system given during the
installation of the operating system. The name of the system used in the example shown in
Figure
9.3 is eagle.
Current Date and Time (DDD, DD MMM YYYY, HH:MM)
The third item in the SOS banner is the current date and time:
DDD denotes the day of the week.
DD denotes the day of the month.
MMM denotes the month.
YYYY denotes the year.
HH:MM denotes the hour and minutes.
Elapsed Time (E: HH:MM:SS)
The fourth item displayed in the SOS banner is the elapsed time (E:HH:MM:SS), which is the time
counted in hours, minutes, and seconds that has passed since you started the current session of
SOS. This elapsed time measurement is especially valuable when viewing cumulative statistics.
For further information, refer to
"Display cumulative stats".
To reset the elapsed time to zero, type r from any SOS display screen.
Current Interval (I: MM:SS)
The last item displayed in the SOS banner is the current interval (I: MM:SS). The current interval
is the amount of time in minutes and seconds accumulated since SOS last updated the screen.
The measurements reported on any SOS display screen are valid for the current interval.
By default, the interval refresh rate is 60 seconds. You can adjust this rate from the Main Options
Menu screen. For further information, refer to
"Screen refresh interval in seconds".
Assuming the interval refresh rate is 60 seconds, the current interval displayed in the SOS banner
should be I: 01:00. However, if at some point during the measurement interval the program has to
wait for user input, the interval update will be delayed. For example, when the f key is pressed
from an SOS display screen to "freeze" the current interval, the next update is delayed until the
user enters the command to "unfreeze" the interval.
If the current interval displayed is less than the interval refresh rate, the user pressed the u key
from an SOS display screen to update the performance data mid-interval.
Current Interval Metrics vs. Cumulative Averages
The statistical values expressed in the format "nnn.n" represent measurements for the current
interval (I: MM:SS). The values in brackets, [nnn.n], represent cumulative averages for the
elapsed interval (E: HH:MM:SS).
Key Indicators of Performance (KIP) Line
The Key Indicators of Performance (KIP) line can be displayed just below the SOS banner. This
option is invoked when the Display Key Indicators of Performance option is enabled from the SOS
Main Option Menu screen.
Figure 9.4 SOS Global Summary screen: Key Indicators of Performance (KIP) line
The purpose of the KIP line is to display statistics associated with the primary indicators of
system performance. The data displayed in the KIP line is configurable. By default, it shows Total
Busy, High Pri, and Read Hit data for the current interval.
Total Busy
The Total Busy value displayed in the KIP line is the percentage of time the CPU spent executing
the following activities instead of being in a pause or idle state:
Processing user and system process code
Processing interrupts
Processing context switches
Managing main memory
Managing traps
High Pri
The High Pri value displayed in the KIP line is the percentage of time the CPU spent executing
high priority processes during the current interval.
Read Hit
The Read Hit value displayed in the KIP line is the read hit percentage for the current interval.
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NOTE By editing the soskip text file located in the /etc/opt/lps/cfg directory, you can redefine the variables to display in the KIP line. For information about editing the soskip file, see "SOS soskip File".
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GLOBAL
The GLOBAL statistics portion of the Global Summary screen contains a simple bar graph that
summarizes activity levels system-wide.
GLOBAL (Left Column)
CPU%
The CPU% bar graph (the left portion of the GLOBAL statistics) shows the percentage of CPU
time expended during the current measurement interval on various activities.
Figure 9.5 SOS Global Summary screen: GLOBAL (left column)
Each letter-width space on the CPU% bar graph represents approximately 2 percent of the CPUs
time for the current interval. The code letters correspond to the CPU activities described in
Table
9.1. Where a block of spaces on the bar graph is bordered by two instances of one code letter
(e.g., S...S), that corresponding activity (e.g., executing system calls and code) would account for
the CPU% range bordered by the two letters.
For example, the CPU% bar shown in
Figure 9.5 indicates the following:
14 percent of CPU time in the current interval was spent executing processes with a negative nice value in user mode.
14 percent of CPU time was spent executing system calls and code (in kernel mode).
2 percent of CPU time was spent executing system interrupt handling code.
4 percent of CPU time was spent managing virtual memory.
The code letters used in the CPU% bar graph are described in
Table 9.1.
Table 9.1 CPU%
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Code
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Statistic
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Description
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C
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Context Switch
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The percentage of time managing context switches between processes.
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I
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Interrupt
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The percentage of time executing system interrupt handling code.
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M
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Memory
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The percentage of time managing virtual memory.
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N
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Nice
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The percentage of time executing processes w/a nice value in user mode.
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R
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Real Time
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The percentage of time executing real-time processes in user mode.
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S
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System
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The percentage of CPU time spent executing system calls and code (in kernel mode). This does not include time spent performing context switches or idle time.
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T
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Trap
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The percentage of time managing traps.
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U
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User Mode
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The percentage of CPU time spent executing user program code with a nice value of 20 and without any special priority .
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W
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Wait
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The amount of idle time the CPU spent waiting for a disk I/O to complete.
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X
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Negative Nice
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The percentage of time executing processes with a negative nice value in user mode.
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states or activities
RHit%
The RHit% bar represents the buffer cache read hit percentage.
WHit%
The WHit% bar represents the write hit percentage.
IO/s
The IO/s bar represents the disk I/O rate. This is the number of physical reads and writes per
second for each type of physical I/O. Similarly to the CPU% bar (see
"CPU%"), specific code
letters in the bar graph tell you how many of each type of physical I/Os were accumulated in the
current interval. Each of these code letters are listed and described in
Table 9.2.
Table 9.2 Physical I/Os
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Code
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Physical I/O
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Description
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U
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User File System
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The number of user file system physical I/Os accumulated in the current interval.
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S
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System
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The number of system physical I/Os accumulated in the current interval.
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V
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Virtual Memory
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The number of virtual memory physical I/Os accumulated in the current interval.
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R
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Raw
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The number of raw physical I/O's accumulated in the current interval.
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GLOBAL (Right Column)
The scale for the next four global statistics ranges from 2 to 20. A value greater than 20 is
represented by a trailing greater than character (>).
Figure 9.6 SOS Global Summary screen: GLOBAL (right column
Each data item in the right column of the GLOBAL statistics is described in
Table 9.3.
Table 9.3 SOS Global data items
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Data Items
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Description
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RunQ Len
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The average number of processes in the CPU run queue during the current interval.
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Pg Out/s
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The number of page outs per second.
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Deact b/s
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The number of deactivated bytes per second.
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I/O QLen
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The average number of disk I/O requests pending for all disks during the current interval.
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PROCESS SUMMARY
After reviewing the general state of global resources, the next logical step in analyzing a system’s
performance is to observe individual processes. It is important to find out which users are running
which programs and what kinds of resources those programs are consuming. The primary
purpose of the PROCESS SUMMARY portion of the Global Summary screen is to help you to
identify key resources consumed by various processes on the system.
To examine the CPU usage, disk I/O usage, and wait state information for a process, open the
Process Detail screen. For further information, see
"SOS Process Detail".
PROCESS SUMMARY Display Options
The PROCESS SUMMARY section is included in the Global Summary screen by default when
the SOS program is started. However, this information can be suppressed. For instructions, refer
to
"Display process information".
You can configure the PROCESS SUMMARY display in the following ways:
Display or suppress the extended process line.
Display either the total and I/O percentages or the read and write counts.
Display all processes or only the active processes.
Display or suppress attached processes.
Display or suppress detached processes.
Display or suppress system processes.
Display or suppress processes that have died.
Apply a process logon filter.
Apply a process sort option.
Display sorted processes in either ascending or descending order.
Set a maximum number of processes to display.
PROCESS SUMMARY Data Items
Figure 9.7 SOS Global Summary screen: PROCESS SUMMARY
The contents of each PROCESS SUMMARY column (shown in
Figure 9.7) are described in the
next table.
Table 9.4 SOS Process Summary data items
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Data Item
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Description
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PID
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The process identification number that uniquely identifies each process running on the system.
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Name
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The process name.
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User Name
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The name of the user that owns (or creates) each process running on the system.
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TTY
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"TTY" is defined in SOS as the special device file of the terminal to which the process is attached. The TTY column will show three dashes (---) for processes that are not attached to a terminal (processes such as daemons and batch jobs).
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CPU%
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The CPU% column shows the percentage of system-wide CPU time that was used by each process. This is normalized for multiple-processors. In other words, all CPU% values added together should never exceed 100 (percent).
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Nic
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The Nic (Nice) column displays the nice value associated with each process.This value, ranging from 0 to 39 (the default is 20), is a determining factor when a process’s priority is recalculated.
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