Messages in this thread | | | Date | Tue, 7 Feb 2012 08:31:22 +0800 | Subject | Re: [patch]block: fix ioc locking warning | From | Shaohua Li <> |
| |
2012/2/7 Tejun Heo <tj@kernel.org>: > On Mon, Feb 06, 2012 at 09:27:06AM -0800, Tejun Heo wrote: >> It's one wq scheduling on exit for any task which has issued an IO. I >> don't think it would matter except for task fork/exit microbenchs (or >> workloads which approximate to that). I'll get some measurements and >> strip the optimization if it doesn't really show up. > > I'm still playing with test methods and getting numbers but the > following is the simplified one of the three setups I'm playing with - > the current one, simplified and no optimization. There *seems* to be > appreciable performance degradation on fork/exit w/ ioc microbenchs so > I'm likely to go with the following. I'll post when I know more. Hi, Since you are talking about performance, one of our microbenchmark (swap) shows a regression. Alex bisect it to be b2efa05265d62bc2, which is related to the ioc change. A little strange to me, don't expect such change can cause performance issue. I haven't double check the issue, but if you have ideas, please let me know.
Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |