The System Activity tool is a series of commands that lets you
capture and work with the data produced by the WRKSYSACT system
command. This provides performance information for jobs/tasks that
have occurred during one or more intervals. The SYSACT tool can be
helpful in reviewing performance characteristics such as CPU usage,
I/O counts and a breakdown of reads/writes for data base and non-data
base activity.
The system WRKSYSACT command
----------------------------
WRKSYSACT was part of the performance tools, but is now a system
command.
WRKSYSACT allows either an interactive approach to view the data or
the ability to create an outfile.
If an outfile is specified, a batch job is submitted. The outfile is
always QAITMON with a default library name of QPFRDATA. An interval
of time in seconds and the number of intervals that you want to
capture information for may be specified. No data is written until
all intervals are complete. The command is always submitted to the
QBATCH job queue in QGPL. The job queue is shipped as a 'single job
at a time' job queue which makes it awkward to determine when the job
will run. The data in the specified output file is always replaced
thus making it awkward to compare information at different times of
the day or on different days.
CPU time is reported in units where each unit is 4096 microseconds.
No command is provided to work with the data.
Benefits of using the SYSACT tool
---------------------------------
The SYSACT tool provides a CAPSYSACT command which allows WRKSYSACT
to run from the QSYSNOMAX job queue thus allowing you to control when
the performance information should be gathered.
A separate job is also run from QSYSNOMAX to copy the data when it is
complete to the TAA file SYSACTP. You control when the data is
cleared by using the MBROPT parameter on CAPSYSACT. This allows
different time periods to be compared.
A TAA DSP command works with the data in SYSACTP to provide basic
performance information. A query may be written for specific
comparisons.
Getting started with SYSACT
---------------------------
** As an *ALLOBJ user, ensure the QAITMON file in QPFRDATA is
created by entering:
WRKSYSACT OUTPUT(*FILE) INTERVAL(1) NBRITV(1)
Wait for the message that says WRKSYSACT is complete. This
creates the QAITMON file in QPFRDATA which is used by the
SYSACT tool.
** As an *ALLOBJ user, create the SYSACTP file in a library of
your choice (a library on your library list is best):
CRTSYSACT SYSACTLIB(xxx)
** If the library is not on your library list, add it.
ADDLIBLE LIB(xxx)
** Capture the system activity by prompting for CAPSYSACT. The
defaults are for 10 second intervals and 5 intervals. This
means that statistics will be accumulated for all jobs that
were running during the interval (including system jobs) and
that 5 intervals should be taken. Keep both numbers low until
you familiarize yourself with the tool. Enter the command
with the defaults:
CAPSYSACT
This submits two batch jobs.
The first job (WRKSYSACT) will run the system command I
WRKSYSACT. The job is submitted in a 'held' status, moved to
the QSYSNOMAX job queue, and then released. The data always
written to the QAITMON file (member QAITMON) in QPFRDATA.
The second job (CPYSYSACT) also runs from the QSYSNOMAX job
queue and waits for the first job to complete. When WRKSYSACT
completes, it copies all data from all intervals and replaces
the data in the QAITMON file in QPRFDATA. CPYF is then used
to copy the data to the SYSACTP file that was created
previously. Records are added to the SYSACTP file (not
replaced).
You should see a completion message for the CPYSYSACT job
about one minute after entering CAPSYSACT.
** Use the display command to display the data.
DSPSYSACT
A display will appear with the data in a basic format
describing each job that ran during each interval. The
qualified job name is described along with the date and time
of the interval. CPU usage, total I/O activity and the number
of data base reads/writes and non-data base reads/writes are
shown.
** After capturing information, you would normally run the
DSPSYSACT with defaults to assist in determining what you want
to select on to minimize the amount of output.
After reviewing the information, you may want to run it again
and specify some selection criteria. For example, you may
want to look at a specific job or user which can be specified
on DSPSYSACT.
** The THRESHOLD parameter on DSPSYSACT allows only the jobs that
meet or exceed a minimum threshold to be listed.
The default is for TYPE(*CPU), but you could specify a value
such as *TOTALIO. The THRESHOLD parameter works with the TYPE
parameter. For example, you can list only those jobs that
have more than 100 I/Os by specifying:
DSPSYSACT TYPE(*TOTALIO) THRESHOLD(100)
** The FORMAT parameter can be used to focus on either the
'reads' or 'writes' that have occurred. For example, you can
specify:
DSPSYSACT FORMAT(*READS) TYPE(*SYNDBR)
THRESHOLD(5)
This will describe the jobs that have had at least 5 data base
'synchronous reads' during an interval.
** You should clear the SYSACTP file if you are no longer
interested in the data. No special command is provided. Use
the system command:
CLRPFM FILE(SYSACTP)
SYSACT escape messages you can monitor for
------------------------------------------
None. Escape messages from based on functions will be re-sent.
CRTSYSACT Command parameters *CMD
----------------------------
SYSACTLIB The name of the library where the SYSACTP file will
be created.
SRCLIB The source library to use for the QATTDDS file
source. The default is *TAAARC.
A specific user library may be named, but the source
file must be QATTDDS.
AUT The authority to the SYSACTP file. The default is
*USE which allows any user to use DSPSYSACT after an
authorized user runs CAPSYSACT. An AUT value of
*CHANGE, *LIBCRTAUT, or *EXCLUDE could also be
entered. Only a user with *CHANGE authority may use
CAPSYSACT.
CAPSYSACT Command parameters *CMD
----------------------------
INTERVAL The interval length in number of seconds. The
default is 10. It must be a number between 1 and
900.
For example, if 10 is used, the system will write a
summary record for each job or task that was active
during a 10 second interval.
INFTYPE The type of information to be captured. The default
is *JOBS which differs from the WRKSYSACT default of
*ALL. *TASKS or *ALL (meaning both *JOBS and
*TASKS) may be specified.
NBRITV The number of intervals to capture information for.
5 is the default. It must be a number between 1 and
900.
MBROPT The member option for the SYSACTP file.
*ADD is the default to add records to the SYSACTP
file.
*REPLACE may be specified to clear the file before
adding any records to SYSACTP.
SYSACTLIB The name of the library where the SYSACTP file
exists that was created by CRTSYSACT. *LIBL is the
default. A specific library of *CURLIB may be
entered.
DSPSYSACT Command parameters *CMD
----------------------------
FORMAT The format of the output. The parameter works in
conjunction with the TYPE parameter. All formats
include the job/task name specifics, the date/time,
CPU usage, and Total I/O used.
*BASIC is the default. This provides basic
performance information which combines the totals
for synchronous and asynchronous values.
*READS may be specified to provide detail
performance information about the types of 'reads'
that have occurred.
*WRITES may be specified to provide detail
performance information about the types of 'writes'
that have occurred.
TYPE The type of information to be displayed. This
parameter works in conjunction with the FORMAT and
THRESHOLD parameters. The TYPE determines what the
THRESHOLD value will be applied to.
*CPU is the default for the amount of CPU units. It
may be specified with any TYPE value. CPU time is
reported by WRKSYSACT in units where each unit is
4096 microseconds.
*TOTALIO may be specified for the number of I/Os.
It may be specified with any TYPE value.
*DBR may be specified for the number of data base
reads. This a combination of both synchronous and
asynchronous reads. It may only be specified for
FORMAT(*BASIC).
*DBW may be specified for the number of data base
writes. This a combination of both synchronous and
asynchronous writes. It may only be specified for
FORMAT(*BASIC).
*NONDBR may be specified for the number of non-data
base reads. This a combination of both synchronous
and asynchronous reads. It may only be specified
for FORMAT(*BASIC).
*NONDBW may be specified for the number of non-data
base writes. This a combination of both synchronous
and asynchronous writes. It may only be specified
for FORMAT(*BASIC).
*SYDBR may be specified for the number of
synchronous data base reads. It may only be
specified for FORMAT(*READS).
*ASYDBR may be specified for the number of
asynchronous data base reads. It may only be
specified for FORMAT(*READS).
*SYDBW may be specified for the number of
synchronous data base writes. It may only be
specified for FORMAT(*WRITES).
*ASYDBW may be specified for the number of
asynchronous data base writes. It may only be
specified for FORMAT(*WRITES).
*SYNDBR may be specified for the number of
synchronous non-data base reads. It may only be
specified for FORMAT(*READS).
*ASYNDBR may be specified for the number of
asynchronous non-data base reads. It may only be
specified for FORMAT(*READS).
*SYNDBW may be specified for the number of
synchronous non-data base writes. It may only be
specified for FORMAT(*WRITES).
*ASYNDBW may be specified for the number of
asynchronous non-data base writes. It may only be
specified for FORMAT(*WRITES).
THRESHOLD The threshold of value for the TYPE value to allow
the job to appear in the listing. For example, if
TYPE(*TOTALIO) is specified with THRESHOLD(10), the
job must have at least 10 I/Os to appear in the
listing. The value must be greater than 0.
PERIOD A selection by date/time of the records in SYSACTP.
The beginning date defaults to *CURRENT meaning
today's date. *BEGIN may be specified (meaning the
first record in the file) or a specific date may be
entered in job format.
The beginning time defaults to *AVAIL meaning the
first time of the beginning date. A specific time
may be entered in HHMMSS format.
The ending date defaults to *CURRENT meaning today's
date. *END may be specified (meaning the record in
the file), or *BGNDATE (meaning the same date as the
beginning date, or a specific date may be entered in
job format.
The ending time defaults to *AVAIL meaning the last
time of the ending date. A specific time may be
entered in HHMMSS format.
JOB The job name to be selected. *ALL is the default
for all jobs. A specific job or a generic job name
may also be entered.
USER The user name to be selected. *ALL is the default
for all users. A specific user or a generic user
name may also be entered.
JOBNBR The job number to be selected *ALL is the default
for all job numbers. A specific job number may also
be entered.
SYSACTLIB The name of the library where the SYSACTP file
exists. *LIBL is the default. A specific library
of *CURLIB may be entered.
OUTPUT How to output the results. * is the default to
display a listing if the command is entered
interactively.
If the command is entered in batch or *PRINT is
specified, a spooled file is created.
Restrictions
------------
You must have *ALLOBJ authority to use CRTSYSACT.
Prerequisites
-------------
The following TAA Tools must be on your system:
CHKALLOBJ Check *ALL object special authority
CHKDBFMBR Check data base file member
CVTTIM Convert time
EDTVAR Edit variable
RSNLSTMSG Resend last message
RTVDAT Retrieve date
RTVJOBSTS Retrieve job status
RTVSBMJOB Retrieve submitted job
RTVSYSVAL3 Retrieve system value 3
SNDCOMPMSG Send completion message
SNDESCINF Send escape information
SNDESCMSG Send escape message
SNDSTSMSG Send status message
Implementation
--------------
None, the tool is ready to use.
Objects used by the tool
------------------------
Object Type Attribute Src member Src file
------ ---- --------- ---------- ----------
DSPSYSACT *CMD TAASYTZ QATTCMD
CRTSYSACT *CMD TAASYTZ2 QATTCMD
CAPSYSACT *CMD TAASYTZ3 QATTCMD
TAASYTZC *PGM CLP TAASYTZC QATTCL
TAASYTZC2 *PGM CLP TAASYTZC2 QATTCL
TAASYTZC3 *PGM CLP TAASYTZC3 QATTCL
TAASYTZC13 *PGM CLP TAASYTZC13 QATTCL
TAASYTZR *PGM RPG TAASYTZR QATTRPG
TAASYTZP *FILE PF TAASYTZP QATTDDS
Structure
---------
DSPSYSACT Cmd
TAASYTZC CL pgm
TAASYTZR RPG Pgm
CRTSYSACT Cmd
TAASYTZC2 CL pgm
CAPSYSACT Cmd
TAASYTZC3 CL pgm
TAASYTZC13 CL pgm submitted by TAASYTZC3
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