On Tue, Nov 19, 2019 at 08:18:04AM +1100, Dave Chinner wrote: > On Mon, Nov 18, 2019 at 09:56:33PM +0530, Srikar Dronamraju wrote: > > * Dave Chinner <david@xxxxxxxxxxxxx> [2019-11-16 10:40:05]: > > > > > On Fri, Nov 15, 2019 at 03:08:43PM +0800, Ming Lei wrote: > > > > On Fri, Nov 15, 2019 at 03:56:34PM +1100, Dave Chinner wrote: > > > > > On Fri, Nov 15, 2019 at 09:08:24AM +0800, Ming Lei wrote: > > > > I can reproduce the issue with 4k block size on another RH system, and > > > > the login info of that system has been shared to you in RH BZ. > > > > > > > > 1) > > > > > > Almost all the fio task migrations are coming from migration/X > > > kernel threads. i.e it's the scheduler active balancing that is > > > causing the fio thread to bounce around. > > > > > > > Can we try with the below patch. > > That makes things much, much worse. Yeah, it is same with my test result, basically the fio io thread migration counts is increased from 5k to 8k. Thanks, Ming