On Thu, 2008-02-21 at 11:48 -0500, Steven Rostedt wrote: > On Thu, 21 Feb 2008, Gregory Haskins wrote: > > > From: Peter W.Morreale <[EMAIL PROTECTED]> > > > > In wakeup_next_waiter(), we take the pi_lock, and then find out whether > > we have another waiter to add to the pending owner. We can reduce > > contention on the pi_lock for the pending owner if we first obtain the > > pointer to the next waiter outside of the pi_lock. > > > > This patch adds a measureable increase in throughput. > > I see how this may decrease contention (slightly less time in holding the > pi_lock). But, please, when stating something like: "adds a measurable > increase in throughput", show the benchmark numbers. > > -- Steve >
Approximately 3% to the dbench benchmark we used. My "standard" sanity check was to mount a ramfs filesystem and execute: dbench -t 10 30 five times and generate an average from the reported "Throughput" numbers displayed by the runs. dbench was chosen merely because of the contention on dcache_lock. Best, -PWM -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
