irqbalance problem on Oracle X5-2

[Mohsin Zaidi]

I'm using the irqbalance daemon with the following config file. The
only thing I've changed is the banned CPUs list, and I've banned all
but CPUs #1 and #37. Interrupts *never* go to #1, and go to #18 and
#37, even though #18 has also been banned.

# irqbalance is a daemon process that distributes interrupts across
# CPUS on SMP systems. The default is to rebalance once every 10
# seconds. This is the environment file that is specified to systemd via the
# EnvironmentFile key in the service unit file (or via whatever method the init
# system you're using has.
#
# ONESHOT=yes
# after starting, wait for a minute, then look at the interrupt
# load and balance it once; after balancing exit and do not change
# it again.
#IRQBALANCE_ONESHOT=

#
# IRQBALANCE_BANNED_CPUS
# 64 bit bitmask which allows you to indicate which cpu's should
# be skipped when reblancing irqs. Cpu numbers which have their
# corresponding bits set to one in this mask will not have any
# irq's assigned to them on rebalance
#
#IRQBALANCE_BANNED_CPUS=
IRQBALANCE_BANNED_CPUS=000000ff,ffffffdf,fffffffd

#
# IRQBALANCE_ARGS
# append any args here to the irqbalance daemon as documented in the man page
#
#IRQBALANCE_ARGS=
Regards,
Mohsin


On Wed, Nov 18, 2015 at 10:28 AM, Neil Horman <nhorman at tuxdriver.com> wrote:
> On Wed, Nov 18, 2015 at 10:04:56AM -0500, Mohsin Zaidi wrote:
>> Sorry about that, Neil.
>>
>> I haven't specified any hint policy in IRQBALANCE_ARGS (for the daemon).
>> Regards,
>> Mohsin
>>
> Ok, well, I'm at a bit of a loss.  irqbalance, based on your output from the
> debug log, is working properly, presuming you actually listed cpus 18 and 37 as
> your only unbanned one, which you indicate is the opposite of what you've
> configured.
>
> Can you please send me the command line you use to start irqbalance?
>
> Neil
>
>>
>> On Wed, Nov 18, 2015 at 6:36 AM, Neil Horman <nhorman at tuxdriver.com> wrote:
>> > On Fri, Nov 13, 2015 at 04:39:08PM -0500, Neil Horman wrote:
>> >> On Fri, Nov 13, 2015 at 01:39:20PM -0500, Mohsin Zaidi wrote:
>> >> > Thanks for your reply, Neil.
>> >> >
>> >> > Yes, when I manually set the irq affinity to avoid #18, it works.
>> >> >
>> >> > I just downloaded and applied the latest irqbalance code, but it's
>> >> > showing the same behavior.
>> >> >
>> >> What hint policy are you using?
>> >>
>> >> Neil
>> >>
>> > Ping, any response regarding hint policy?
>> >
>> > Neil
>> >
>>