dispadmin(1M) System Administration Commands dispadmin(1M)NAMEdispadmin - process scheduler administration
SYNOPSISdispadmin-l
dispadmin-c class {-g [-r res] | -s file}
dispadmin-d [class]
DESCRIPTION
The dispadmin command displays or changes process scheduler parameters
while the system is running.
dispadmin does limited checking on the values supplied in file to ver‐
ify that they are within their required bounds. The checking, however,
does not attempt to analyze the effect that the new values have on the
performance of the system. Inappropriate values can have a negative
effect on system performance. (See System Administration Guide:
Advanced Administration.)
OPTIONS
The following options are supported:
-c class
Specifies the class whose parameters are to be displayed or
changed. Valid class values are: RT for the real-time class, TS for
the time-sharing class, IA for the inter-active class, FSS for the
fair-share class, and FX for the fixed-priority class. The time-
sharing and inter-active classes share the same scheduler, so
changes to the scheduling parameters of one will change those of
the other.
-d [class]
Sets or displays the name of the default scheduling class to be
used on reboot when starting svc:/system/scheduler:default. If
class name is not specified, the name and description of the cur‐
rent default scheduling class is displayed. If class name is speci‐
fied and is a valid scheduling class name, then it is saved in dis‐
padmin's private configuration file /etc/dispadmin.conf. Only
super-users can set the default scheduling class.
-g
Gets the parameters for the specified class and writes them to the
standard output. Parameters for the real-time class are described
in rt_dptbl(4). Parameters for the time-sharing and inter-active
classes are described in ts_dptbl(4). Parameters for the fair-share
class are described in FSS(7). Parameters for the fixed-priority
class are described in fx_dptbl(4).
The -g and -s options are mutually exclusive: you may not retrieve
the table at the same time you are overwriting it.
-l
Lists the scheduler classes currently configured in the system.
-r res
When using the -g option you may also use the -r option to specify
a resolution to be used for outputting the time quantum values. If
no resolution is specified, time quantum values are in millisec‐
onds. If res is specified it must be a positive integer between 1
and 1000000000 inclusive, and the resolution used is the reciprocal
of res in seconds. For example, a res value of 10 yields time quan‐
tum values expressed in tenths of a second; a res value of 1000000
yields time quantum values expressed in microseconds. If the time
quantum cannot be expressed as an integer in the specified resolu‐
tion, it is rounded up to the next integral multiple of the speci‐
fied resolution.
-s file
Sets scheduler parameters for the specified class using the values
in file. These values overwrite the current values in memory—they
become the parameters that control scheduling of processes in the
specified class. The values in file must be in the format output by
the -g option. Moreover, the values must describe a table that is
the same size (has same number of priority levels) as the table
being overwritten. Super-user privileges are required in order to
use the -s option.
Specify time quantum values for scheduling classes in system clock
ticks, and not in constant-time units. Time quantum values are
based on the value of the kernel's hz variable. If kernel variable
hires_tick is set to 1 to get higher resolution clock behavior, the
actual time quanta will be reduced by the order of 10.
The -g and -s options are mutually exclusive: you may not retrieve
the table at the same time you are overwriting it.
EXAMPLES
Example 1 Retrieving the Current Scheduler Parameters for the real-time
class
The following command retrieves the current scheduler parameters for
the real-time class from kernel memory and writes them to the standard
output. Time quantum values are in microseconds.
dispadmin-c RT -g -r 1000000
Example 2 Overwriting the Current Scheduler Parameters for the Real-
time Class
The following command overwrites the current scheduler parameters for
the real-time class with the values specified in rt.config.
dispadmin-c RT -s rt.config
Example 3 Retrieving the Current Scheduler Parameters for the Time-
sharing Class
The following command retrieves the current scheduler parameters for
the time-sharing class from kernel memory and writes them to the stan‐
dard output. Time quantum values are in nanoseconds.
dispadmin-c TS -g -r 1000000000
Example 4 Overwriting the Current Scheduler Parameters for the Time-
sharing Class
The following command overwrites the current scheduler parameters for
the time-sharing class with the values specified in ts.config.
dispadmin-c TS -s ts.config
FILES
/etc/dispadmin.conf
Possible location for argument to -s option.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │SUNWcs │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOpriocntl(1), svcs(1), svcadm(1M), priocntl(2), fx_dptbl(4),
rt_dptbl(4), ts_dptbl(4), attributes(5), smf(5), FSS(7)DIAGNOSTICSdispadmin prints an appropriate diagnostic message if it fails to over‐
write the current scheduler parameters due to lack of required permis‐
sions or a problem with the specified input file.
NOTES
The default scheduling class setting facility is managed by the service
management facility, smf(5), under the service identifier:
svc:/system/scheduler:default
Administrative actions on this service, such as enabling, disabling, or
requesting restart, can be performed using svcadm(1M). Note that dis‐
abling the service while it is running will not change anything. The
service's status can be queried using the svcs(1) command.
SunOS 5.11 7 Oct 2008 dispadmin(1M)