 |
Index for
Section 8 |
|
 |
Alphabetical
listing for C |
|
 |
Bottom of
page |
|
class_admin(8)
NAME
class_admin - Administer daemons and databases for class scheduling.
SYNOPSIS
/usr/sbin/class_admin [subcommand[, subcommand]...]
DESCRIPTION
Class scheduling allows you to organize users and groups into classes and
specify the maximum percentage of CPU usage permitted each class. The
class_admin utility is used to set up and maintain class databases and to
start and stop the class scheduler. These operations are performed through
utility subcommands, which are listed and described in the "Subcommands"
section. Read the information in class_scheduling(4) if you are unfamiliar
with class scheduling. That reference page includes conceptual information,
guidelines, and restrictions that are not repeated here and apply to both
the class_admin utility and the class scheduling APIs.
All class_admin subcommands execute in the context of a soft partition
(processor set). The class_admin utility maintains different class
scheduling databases for different partitions, and you must enable class
scheduling on each partition for which you maintain a class scheduling
database. If user-defined partitions do not exist, the default partition is
the only partition on the system and contains all system CPUs. This
partition exists even after user-defined partitions have been created; in
which case, it contains all CPUs that have not been allocated to a user-
defined partition. When you enter the class_admin command without a setp
pset_num subcommand, the default partition is your context. You can enter a
setp subcommand at the utility prompt to change partition context.
The class_admin command can be run interactively or non-interactively.
Non-interactive mode allows class_admin to be run from within a script,
which makes it easy to enable class scheduling at system startup through
use of an init script. (See init(8).) To run class_admin non-interactively,
specify one or more subcommands as arguments on the utility command line.
Interactive mode is useful after system startup. To run class_admin
interactively, you can invoke class_admin without specifying any arguments,
and then enter all subcommands at the utility prompt. The exception is
that you should include the setp pset_num subcommand at invocation time if
you do not plan to enable class scheduling for the system default
partition.
Database Configuration Parameters
If a class scheduling database does not exist for the partition to which
context is set, the class_admin utility automatically creates a class
database when it starts up. When running the utility interactively, you
supply configuration parameters for the database by answering three
questions. For non-interactive operation, the utility automatically
applies to the database the default answers to these questions. You can
reset configuration parameters at a later time by using the utility's
configure subcommand.
The following questions prompt for database configuration parameters:
1. Shall processes that have not been explicitly assigned to a defined
class be assigned to a "default" class? Enter (yes/no) [no]:
To be class scheduled, a process must be assigned to a class. If you
answer yes to this question, a special class called the "default"
class will be created, and any process that does not belong to the
classes you define will be assigned to this class. If you answer no to
this question, then only those processes that belong to classes
defined by you are class scheduled. Processes owned by root (UID 0)
are not subject to class scheduling.
2. Enforce class scheduling when the CPU is otherwise idle? (yes/no)
[yes]:
If you answer no to this question, the scheduler can allow a class to
exceed its CPU percentage when the partition has idle CPUs. Otherwise,
a class is held to its allotted percentage even if the CPUs in the
partition have no other work.
3. How often do you want the system to reset class usage? Enter number of
seconds (1):
If there are interactive jobs subject to class scheduling, use a small
number (no more than several seconds) to ensure a quick response time.
If only batch jobs are class scheduled, you can enter larger values
because system response time is not an issue.
If you included the enable subcommand on the class_admin command line, your
settings take effect immediately.
Subcommands
add Add one or more identifiers for a group, user, process, process group,
or session to an existing scheduling class. If the specified identifier
is a member of another class, you will be asked whether you want to
move the member.
Syntax:
add class_name type id [id]...
The type argument can be one of the following:
gid To add one or more group identifiers to the class. In this
case, the specified numbers reside in the /etc/group file.
These identifiers will persist in the class scheduling database
across reboots.
uid To add one or more user identifiers to the class. In this case,
the specified numbers reside in the /etc/passwd file. These
identifiers will persist in the class scheduling database
across reboots.
pid To add one or more process identifiers to the class. In this
case, the specified numbers, as shown in the PID column of the
ps command display, persist in the class scheduling database
only as long as those processes are running.
pgrp To add one or more process group identifiers to the class. In
this case, the specified numbers, as shown in the PGID column
of the ps command display, persist in the class scheduling
database only as long as any processes in those process groups
are running.
session To add one or more session identifiers to the class. In this
case, the specified numbers, as shown in the SESS column of the
ps command display, persist in the class scheduling database
only as long as any processes in those sessions are running.
cancel
Remove recent changes to the currently loaded database and go back to
the version last saved to disk.
Syntax:
cancel
change
Change the CPU percentage allotted to a scheduling class. You cannot
specify a CPU percentage that would cause the total of percentages for
all classes in the database to exceed 100%.
Syntax:
change class_name cpu_percentage
create
Create a new scheduling class. The specified name must be unique and
cannot exceed 20 characters. Because a newly created class will be
empty, you must use the add subcommand to populate the class with
members or add process members indirectly through the runclass command
after class scheduling is enabled. You cannot specify a CPU percentage
that would cause the total of percentages for all classes in the
database to exceed 100%.
Syntax:
create class_name cpu_percentage
configure
Set up the basic class scheduling parameters. You will be asked the
three questions discussed in the "Database Configuration Parameters"
section.
Syntax:
configure
delete
Remove one or more member identifiers from an existing scheduling
class.
Syntax:
delete class_name type id [id]...
See the entry for the add subcommand for a list of supported type
values.
destroy
Destroy an existing scheduling class. If the class is not empty, you
will be asked for permission to destroy it anyway.
Syntax:
destroy class_name
disable
Turn off class scheduling for the partition to which context is set.
Note that the kernel will terminate the instance of the scheduler
daemon for that partition.
Syntax:
disable
enable
Turn on class scheduling for the partition to which context is set.
This starts a daemon that periodically examines CPU usage by different
classes and makes adjustments in CPU access according to the class
limits.
Syntax:
enable
exit
Return to the command shell. If there are any unsaved changes to the
current class scheduling database during your session, you will be
asked whether you want to save them. (Same as for quit.)
Syntax:
exit
help
Display online help. If you specify a particular subcommand, the
utility displays the syntax for only that subcommand. Otherwise, the
utility displays a list of all subcommands and their arguments.
Syntax:
help [subcommand]
listp
List all partitons and the status of class scheduling for each.
Syntax:
listp
load
Load the specified class database from disk into memory.
Syntax:
load database_path
The database_path is the path to the class database. By default, class
databases reside in the /etc/class directory and have file names in the
format part.partition.
If you made changes to the database that is currently loaded into
memory and neither cancelled nor saved these changes to disk, the
utility tells you that load operation will destroy unsaved changes and
asks if you still want to proceed with the load operation.
quit
Return to the command shell. If there are any unsaved changes to the
database that is currently loaded into memory, you will be asked
whether you want to save them. (Same as for exit.)
Syntax:
quit
rename
Change the name of an scheduling class.
Syntax:
rename old_class_name new_class_name
save
Write permanent database changes to a file on disk and continue.
Syntax:
save [database_path]
The database_path argument is the pathname for the class database that
you are currently setting up or changing. If you omit this argument,
changes are saved to the disk file of the class database currently
loaded into memory. If you invoked class_admin to set up a new
database, use the show command to see the default name and directory
for the associated file. If you decide to change the default name or
location, remember that the pathname cannot exceed 80 characters.
setp
Set partition context.
Syntax:
setp [pset_id]
If you do not specify pset_id, the system default partition (processor
set 0) is assumed. See also listp.
show
Show the CPU percentage and members for a scheduling class. If you do
not specify a class name, the utility shows this information for all
classes in the currently loaded database.
Syntax:
show [class_name]
stats
List the target and actual CPU utilization for a scheduling class. If
you do not specify a class name, the utility shows CPU utilization for
all classes in the current database.
Syntax:
stats [class_name]
FILES
/etc/class/part.*
Default pathname for a class database, where * represents the
partition.
/usr/sbin/class_daemon
The class scheduler daemon.
SEE ALSO
Commands: ps(1), runclass(1)
Files: class_scheduling(4), processor_sets(4)
Functions: class_add(3), class_change(3), class_change_name(3),
class_close(3), class_configure(3), class_create(3),
class_database_file_exists(3), class_database_modified(3),
class_database_name(3), class_delete(3), class_destroy(3),
class_disable(3), class_get_class_members(3), class_get_classes(3),
class_get_config_stats(3), class_load_database(3), class_open(3),
class_restore_database(3), class_save_database(3)
|
Index for
Section 8 |
|
|
Alphabetical
listing for C |
|
 |
Top of
page |
|