"Luck, Tony" <tony.luck@xxxxxxxxx> writes: > > But the patch went in because the ticket locks were only very slightly > slower in the uncontended case, and they did solve a real problem > for a common two socket platform where the lack of fairness allowed the It was a eight socket platform. I'm not aware of any unfair two socket platforms. > cores on one socket to freeze out the cores on the other socket for > extremely long periods. Very long as a minute in extreme corner cases. So the motivation was more to limit the worst case than to tune a common case. BTW the main problem of ticket locks is that they tend to cooperate badly with hypervisors, they can run into bad convoying issues with the vcpu scheduler. So you probably should have a way to turn them off. -Andi -- ak@xxxxxxxxxxxxxxx -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
|