rcutorture: Do better bin packing
Running the standard set of rcutorture tests on 24 CPUs results in
the following sub-optimal schedule:
----start batch----
TREE07 16
----start batch----
TREE08 16
SRCU-P 8
----start batch----
TREE01 8
TREE02 8
TREE03 8
----start batch----
TREE04 8
TREE05 8
TREE06 8
----start batch----
SRCU-N 4
TINY01 1
TINY02 1
TREE09 1
If one of the eight-CPU runs were to be moved into the first batch,
the test suite would complete in four batches rather than five.
This commit therefore uses a greedy algorithm to re-order the test
entries so that the sequential batching will produce an optimal schedule
in this case:
----start batch----
TREE07 16
SRCU-P 8
----start batch----
TREE08 16
TREE01 8
----start batch----
TREE02 8
TREE03 8
TREE04 8
----start batch----
TREE05 8
TREE06 8
SRCU-N 4
TINY01 1
TINY02 1
TREE09 1
Please note that this is still not an optimal bin-packing algorithm,
however, it does produce optimal solutions for most common scenarios.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
1 file changed