[CentOS] Re: irqbalance is dead, can not shutdown

Tue Apr 4 21:01:27 UTC 2006
Steven <asterisk at tescogroup.com>

I get better performance when I disable it.

I put my PRI card interrupts on 1 CPU and my RAID controller, Eth, etc. on the other.
This is a boost for my PRI cards. (digium cards for asterisk VOIP PBX)
These cards produce 1000 interrupts per second.

irqbalance was reassigning the CPU for handling the interrupts on the PRI cards every few seconds.  During the switch, I would drop 
a few interrupts.



"James Olin Oden" <james.oden at gmail.com> wrote in message 
news:ac921f990604041013l641b92d8wd98e3dd7aec80ac2 at mail.gmail.com...
On 4/4/06, William L. Maltby <BillsCentOS at triad.rr.com> wrote:
> On Tue, 2006-04-04 at 10:28 -0400, lnthai2002 at aim.com wrote:
> > After updating to centos 4.3, I notice a failure in terminating
> > irqbalance whenever i shutdown the system. Checking the services after
> > the system reboot i see the error in irqbalance:
> > "irqbalance dead but subsys locked"
> > Can anyone tell me what irqbalance is
As the other person said it distrubutes IRQ's across multiple
processors in an SMP system.  You don't want to disable this as it
will impact system performance.  Just as a quick explanation, by
default all of the IRQ's (the signals that let hardware devices notify
the cpu and by extension device drivers know that they need servicing)
end up on one processor (at least on Intel like architectures).  The
OS though can balance them across muliple processors which is
typically more efficient (share the load sort of thing).  I don't know
the algorithms that irqbalance uses to distribute the IRQ's but it
definately makes things more efficient.
So again you don't want to disable this (unless your on a single
processor machine, and then its a moot point; in this case disable
away using chkconfig).

What I would sugest is filing a bugzilla report at bugzilla.redhat.com.