intrbald(1M) intrbald(1M)
NAME
intrbald - daemon for balancing interrupts
SYNOPSIS
interval |
DESCRIPTION
Balancing interrupts is a process which distributes interrupts across the available CPUs in an optimal fashion. This action is performed
by (see intctl(1M)).
Performing frequent CPU migrations between system partitions may require you to perform periodic balancing of interrupts. This is espe-
cially true with systems that use WLM (Workload Manager), iCAP (Instant Capacity), and vPars (Virtual Partitions) products. If the fre-
quency of CPU migration is high, then balancing of interrupts should be performed more frequently.
The daemon monitors the system for imbalance in interrupt distribution. If an imbalance is detected after the specified interval executes
to balance the interrupt distribution. uses the parameters from the configuration file for balancing the interrupts. For more information
about the command, see intctl(1M) and the configuration file.
The daemon is started from the general purpose sequencer script (see rc(1M)), at run level 2 and is killed at run level 1. By default, the
daemon is not enabled. The daemon configuration file must be edited and the parameter set to in order to enable running the daemon. After
setting to for the first time, you can start the daemon manually by executing the script Otherwise, the daemon will automatically start the
next time the system is restarted.
Any actions performed by the daemon are logged in and details of interrupt migrations performed will be logged in the file
Options
recognizes the following options:
Instructs the running daemon to reexamine the configuration file
If the parameter has been updated, then the running daemon uses the new value. If the parameter is set to then the running
daemon stops executing.
The daemon checks if the system requires any balancing of interrupts
after interval seconds; the valid range is 5 seconds to seconds (see limits(5)).
This value can also be specified persistently in the configuration file by setting the parameter.
The default value is 60 seconds.
Setting this value too small can cause unnecessary interrupt migrations.
Gracefully kills the running daemon.
intrbald rc Configuration File
is the configuration file.
The following parameters can be persistently specified in this configuration file:
Specifies if the daemon should be started automatically during the system bootup process by the script. The daemon will only be started
automatically if this parameter is set to
NOTE: This value is by default. Before using the daemon, needs to be changed to in the file. Then the daemon needs to be started,
either manually by running or it will be started automatically at next boot via the script.
The daemon checks if the system requires any
interrupt balancing after this interval. The interval is specified in seconds; the valid range is 5 seconds to seconds (see lim-
its(5)). The default is 60 seconds.
Setting this value too small could cause unnecessary interrupt migrations.
RETURN VALUE
Exit values are:
Successful completion.
An error condition occurred.
WARNINGS
The command can be executed only by the superuser. This command should be used only by performance analysts for performance tuning pur-
poses. If the interrupts are not redistributed properly, a possible decrease in overall system performance can occur. Some processors can
become overloaded while other processors will not be optimally utilized.
FILES
configuration file. See the section above.
script.
start symbolic link.
kill symbolic link.
daemon log file.
SEE ALSO
intctl(1M), ioscan(1M), rc(1M), limits(5).
intrbald(1M)