On Wed, Jul 5, 2017 at 12:48 PM, Peter Zijlstra <pet...@infradead.org> wrote: > On Wed, Jul 05, 2017 at 11:42:46AM -0400, Ben Guthro wrote: >> Hello, >> >> I've been in the process of updating our kernel in our appliance VM >> from an old LTS kernel (4.1.y) to something a bit more modern (4.9.y) >> - and ran into a performance regression, when our QA team was running >> some regression suites. >> >> >> I bisect this behavior to the following commit, introduced in the 4.9 >> merge window: >> > > Could you test a later kernel that includes commit: > > 1ad3aaf3fcd2 ("sched/core: Implement new approach to scale > select_idle_cpu()") >
(resend without html) Apologies on the delay - it took a bit to get the machines, to run the test. I am happy to report that the kernel at 1ad3aaf3fcd2, seems to regain performance loss from 1b568f0aab, in our test environment. Since 4.9 is an LTS kernel - is this appropriate to suggest to be included in the linux-stable list?