Commit-ID: b5fe223a4bd0217a657ff084e48752c367a8a55f Gitweb: http://git.kernel.org/tip/b5fe223a4bd0217a657ff084e48752c367a8a55f Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> AuthorDate: Thu, 27 Apr 2017 07:52:35 -0700 Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> CommitDate: Thu, 27 Apr 2017 08:35:24 -0700 srcu: Adjust default auto-expediting holdoff The default value for the kernel boot parameter srcutree.exp_holdoff is 50 microseconds, which is too long for good Tree SRCU performance (compared to Classic SRCU) on the workloads tested by Mike Galbraith. This commit therefore sets the default value to 25 microseconds, which shows excellent results in Mike's testing. Reported-by: Mike Galbraith <efault@xxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Tested-by: Mike Galbraith <efault@xxxxxx> --- kernel/rcu/srcutree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 74c283f..87b070d 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -39,7 +39,7 @@ #include "rcu.h" -ulong exp_holdoff = 50 * 1000; /* Holdoff (ns) for auto-expediting. */ +ulong exp_holdoff = 25 * 1000; /* Holdoff (ns) for auto-expediting. */ module_param(exp_holdoff, ulong, 0444); static void srcu_invoke_callbacks(struct work_struct *work); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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