[ltt-dev] [RFC PATCH 0/7] priority-boost urcu

Paul E. McKenney paulmck at linux.vnet.ibm.com
Wed Aug 17 13:22:28 EDT 2011

On Wed, Aug 17, 2011 at 10:08:04AM -0700, Paolo Bonzini wrote:
> On 08/17/2011 07:31 AM, Mathieu Desnoyers wrote:
> >So I guess that in that sense, synchronize_rcu() of MB and QSBR could be
> >merged, is that what you are trying to get at ? (sorry for being slow on
> >the uptake);-)
> Yes, and perhaps MEMBARRIER too---leaving just SIGNAL as the oddball
> one.  That's also why I started doing the futex optimization in
> Did you measure SIGNAL to have better performance in practice than MB?

Yep.  See http://www.rdrop.com/users/paulmck/preprints/, click on
"main paper" and see figures 6 and later.  Note that the "Signal-based
RCU" line is significantly higher than the "General-purpose RCU" line,
and keep in mind that these plots use logscale y axes.

Of course, your mileage may vary.

							Thanx, Paul

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