On Mon, Oct 30, 2017 at 07:27:36AM +0100, Fengguang Wu wrote: > [ 189.480568] perf: interrupt took too long (5132 > 4982), lowering > kernel.perf_event_max_sample_rate to 38000 > [ 189.690660] perf: interrupt took too long (6582 > 6415), lowering > kernel.perf_event_max_sample_rate to 30000 > [ 189.901706] perf: interrupt took too long (8268 > 8227), lowering > kernel.perf_event_max_sample_rate to 24000 > [ 272.841032] perfevents: irq loop stuck! > [ 272.841038] ------------[ cut here ]------------ > [ 272.841046] WARNING: CPU: 9 PID: 5377 at arch/x86/events/intel/core.c:2228 > intel_pmu_handle_irq+0x4a8/0x4c0
So I've not seen this in a fair while; is this new in 4.14? > [ 272.841083] CPU: 9 PID: 5377 Comm: usemem Not tainted 4.14.0-rc6 #1 At least you've got the right kernel this time... :-) > [ 272.841084] Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS > GRRFSDP1.86B.0271.R00.1510301446 10/30/2015 That's a dual socket board for Xeon E5v3, which translates to HSW-EP if google is any good today. That's not a machine I have. Can you see this on other hardware too, like say IVB-EP ?