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To: Dan Williams <dan.j.williams@intel.com>
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Subject: Re: [RFC PATCH 1/2] block: strict rq_affinity
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On 2011-07-22 22:59, Dan Williams wrote:
> Some storage controllers benefit from completions always being steered
> to the strict requester cpu rather than the looser "per-socket" steering
> that blk_cpu_to_group() attempts by default.
> 
> echo 2 > /sys/block/<bdev>/queue/rq_affinity

I have applied this one, with a modified patch description.

I like the adaptive solution, but it should be rewritten to not declare
and expose softirq internals. Essentially have an API from
kernel/softirq.c that can return whether a given (or perhaps just local)
softirq handler is busy or not.


-- 
Jens Axboe