Messages in this thread | | | Date | Sat, 9 Jul 2016 21:26:39 -0700 | From | "Paul E. McKenney" <> | Subject | Odd performance results |
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Hello!
So I ran a quick benchmark which showed stair-step results. I immediately thought "Ah, this is due to CPU 0 and 1, 2 and 3, 4 and 5, and 6 and 7 being threads in a core." Then I thought "Wait, this is an x86!" Then I dumped out cpu*/topology/thread_siblings_list, getting the following:
cpu0/topology/thread_siblings_list: 0-1 cpu1/topology/thread_siblings_list: 0-1 cpu2/topology/thread_siblings_list: 2-3 cpu3/topology/thread_siblings_list: 2-3 cpu4/topology/thread_siblings_list: 4-5 cpu5/topology/thread_siblings_list: 4-5 cpu6/topology/thread_siblings_list: 6-7 cpu7/topology/thread_siblings_list: 6-7
Is this now expected behavior or a fluke of my particular laptop? Here is hoping for expected behavior, as it makes NUMA locality the default for a great many workloads.
Enlightenment?
Thanx, Paul
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