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 [off-list ref]
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