Re: [PATCH] NUMA-Q disable irqbalance

Linus Torvalds
2002-08-13T16:35:32Z

On Tue, 13 Aug 2002, Martin J. Bligh wrote:
:
> This patch is from Matt Dobson. It disables irq_balance for the NUMA-Q
> and makes it a config option for everyone else.

Please don't use negative config options.

I'd much rather have

bool 'IRQ balancing support' CONFIG_IRQ_BALANCE

than some "Disable IRQ balancing?" question.

Also, the explanation should probably explain that a P4 needs manual IRQ
balancing since the P4 broke the Intel-documented round-robin behaviour.

Finally, exactly since IRQ balancing is practically required on P4-SMP, I
really don't think a CONFIG option works. It needs to be configured in on
any kernel that expects to use P4's in an SMP configuration.

In other words, I think this needs to do a dynamic disable (with the
possible exception of a NUMA-Q machine, since that one is already a static
config option and won't have P4's in it).

Linus