Re: SO_REUSEPORT - can it be done in kernel?

Herbert Xu
2011-02-28T04:26:34Z

On Sun, Feb 27, 2011 at 07:45:55PM -0800, Tom Herbert wrote:
> That sounds promising, but receive side will still have problems.
> There is lock contention on the queue as well as cache line bouncing
> on the sock structures. Also multiple threads sleeping on same socket
> typically leads to asymmetric load across the threads (and
> degenerative cases where receiving thread is woken up and other
> threads have already processed all the packets). TCP listener threads
> suffer from these same problems.

IOW this is something that we have to solve anyway. I'm just
being overly cautious here because user-space API changes are
something that we should not enter into lightly.

If this patch was completely internal to the kernel, then I would
have much less of an objection as we can always revert/change it
later on. With a user-space API we don't have that flexibility.

Thanks,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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