IRQBALANCE(1) irqbalance IRQBALANCE(1)
irqbalance - distribute hardware interrupts across processors on a multiprocessor system
The purpose of irqbalance is to distribute hardware interrupts across processors on a mul‐
tiprocessor system in order to increase performance.
Causes irqbalance to be run once, after which the daemon exits.
Causes irqbalance to print extra debug information. Implies --foreground.
Causes irqbalance to run in the foreground (without --debug).
Enables log output optimized for systemd-journal.
-h, --hintpolicy=[exact | subset | ignore]
Set the policy for how IRQ kernel affinity hinting is treated. Can be one of:
exact IRQ affinity hint is applied unilaterally and never violated.
subset IRQ is balanced, but the assigned object will be a subset of the affinity hint.
ignore IRQ affinity hint value is completely ignored.
The default value for hintpolicy is ignore.
Set the threshold at which we attempt to move a CPU into powersave mode If more
than CPUs are more than 1 standard deviation below the average CPU
softirq workload, and no CPUs are more than 1 standard deviation above (and have
more than 1 IRQ assigned to them), attempt to place 1 CPU in powersave mode. In
powersave mode, a CPU will not have any IRQs balanced to it, in an effort to pre‐
vent that CPU from waking up without need.
Add the specified IRQ to the set of banned IRQs. irqbalance will not affect the
affinity of any IRQs on the banned list, allowing them to be specified manually.
This option is addative and can be specified multiple times. For example to ban
IRQs 43 and 44 from balancing, use the following command line: irqbalance
This allows a user to specify the cache level at which irqbalance partitions cache
domains. Specifying a deeper cache may allow a greater degree of flexibility for
irqbalance to assign IRQ affinity to achieve greater performance increases, but
setting a cache depth too large on some systems (specifically where all CPUs on a
system share the deepest cache level), will cause irqbalance to see balancing as
unnecessary. irqbalance --deepestcache=2
The default value for deepestcache is 2.