Re: [PATCH 2/2] md/raid5: exclusive wait_for_stripe

On Mon, Apr 27, 2015 at 10:24:05AM +1000, NeilBrown wrote: > On Fri, 24 Apr 2015 21:39:04 +0800 Yuanhan Liu > wrote: > > > I noticed heavy spin lock contention at get_active_stripe() with fsmark > > multiple thread write workloads. > > > > Here is how this hot contention comes from. We have limi

Re: [PATCH 2/2] md/raid5: exclusive wait_for_stripe

On Fri, 24 Apr 2015 21:39:04 +0800 Yuanhan Liu wrote: > I noticed heavy spin lock contention at get_active_stripe() with fsmark > multiple thread write workloads. > > Here is how this hot contention comes from. We have limited stripes, and > it's a multiple thread write workload. Hence, those st

[PATCH 2/2] md/raid5: exclusive wait_for_stripe

I noticed heavy spin lock contention at get_active_stripe() with fsmark multiple thread write workloads. Here is how this hot contention comes from. We have limited stripes, and it's a multiple thread write workload. Hence, those stripes will be taken soon, which puts later processes to sleep for