Hey, guys and Oleg (yes, I'm singling you out ;p because you're that awesome.) On Sat, Mar 02, 2013 at 01:44:02AM +0800, Lai Jiangshan wrote: > Performance: > We only focus on the performance of the read site. this read site's fast path > is just preempt_disable() + __this_cpu_read/inc() + arch_spin_trylock(), > It has only one heavy memory operation. it will be expected fast. > > We test three locks. > 1) traditional rwlock WITHOUT remote competition nor cache-bouncing.(opt-rwlock) > 2) this lock(lgrwlock) > 3) V6 percpu-rwlock by "Srivatsa S. Bhat". (percpu-rwlock) > (https://lkml.org/lkml/2013/2/18/186) > > nested=1(no nested) nested=2 nested=4 > opt-rwlock 517181 1009200 2010027 > lgrwlock 452897 700026 1201415 > percpu-rwlock 1192955 1451343 1951757 On the first glance, the numbers look pretty good and I kinda really like the fact that if this works out we don't have to introduce yet another percpu synchronization construct and get to reuse lglock. So, Oleg, can you please see whether you can find holes in this one? Srivatsa, I know you spent a lot of time on percpu_rwlock but as you wrote before Lai's work can be seen as continuation of yours, and if we get to extend what's already there instead of introducing something completely new, there's no reason not to (and my apologies for not noticing the possibility of extending lglock before). So, if this can work, it would be awesome if you guys can work together. Lai might not be very good at communicating in english yet but he's really good at spotting patterns in complex code and playing with them. Thanks! -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
