Re: [RFC2 nowrap: PATCH v7 00/18] ILP32 for ARM64

> On 17 Aug 2016, at 13:46, Yury Norov wrote: > > This series enables aarch64 with ilp32 mode, and as supporting work, > introduces ARCH_32BIT_OFF_T configuration option that is enabled for > existing 32-bit architectures but disabled for new arches (so 64-bit > off_t

Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

On 15/03/2017 22:22, Michael S. Tsirkin wrote: Guests running Mac OS 5, 6, and 7 (Leopard through Lion) have a problem: unless explicitly provided with kernel command line argument "idlehalt=0" they'd implicitly assume MONITOR and MWAIT availability, without checking CPUID. We currently

Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

On 03/29/2017 02:11 PM, Radim Krčmář wrote: 2017-03-28 13:35-0700, Jim Mattson: On Tue, Mar 28, 2017 at 7:28 AM, Radim Krčmář <rkrc...@redhat.com> wrote: 2017-03-27 15:34+0200, Alexander Graf: On 15/03/2017 22:22, Michael S. Tsirkin wrote: Guests running Mac OS 5, 6, and 7 (Leopard t

Re: [PATCH v6] kvm: better MWAIT emulation for guests

> Am 11.04.2017 um 19:10 schrieb Jim Mattson : > > This might be more useful if it could be dynamically toggled on and > off, depending on system load. What would trapping mwait (currently) buy you? As it stands today, before this patch, mwait is simply implemented as a

Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

On 04/04/2017 02:39 PM, Radim Krčmář wrote: 2017-04-03 12:04+0200, Alexander Graf: On 03/29/2017 02:11 PM, Radim Krčmář wrote: 2017-03-28 13:35-0700, Jim Mattson: On Tue, Mar 28, 2017 at 7:28 AM, Radim Krčmář <rkrc...@redhat.com> wrote: 2017-03-27 15:34+0200, Alexander Graf: On 15/0

Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

On 04/04/2017 03:13 PM, Radim Krčmář wrote: 2017-04-04 14:51+0200, Alexander Graf: On 04/04/2017 02:39 PM, Radim Krčmář wrote: 2017-04-03 12:04+0200, Alexander Graf: So coming back to the original patch, is there anything that should keep us from exposing MWAIT straight into the guest at all

Re: [PATCH v6] kvm: better MWAIT emulation for guests

On 21.04.17 12:02, Paolo Bonzini wrote: On 12/04/2017 18:29, Michael S. Tsirkin wrote: I don't really agree we do not need the PV flag. mwait on kvm is different from mwait on bare metal in that you are heavily penalized by scheduler for polling unless you configure the host just so. HLT

Re: [PATCH 2/2] x86/idle: use dynamic halt poll

On 17.07.17 11:26, Yang Zhang wrote: On 2017/7/14 17:37, Alexander Graf wrote: On 13.07.17 13:49, Yang Zhang wrote: On 2017/7/4 22:13, Radim Krčmář wrote: 2017-07-03 17:28+0800, Yang Zhang: The background is that we(Alibaba Cloud) do get more and more complaints from our customers

Re: [PATCH 2/2] x86/idle: use dynamic halt poll

On 13.07.17 13:49, Yang Zhang wrote: On 2017/7/4 22:13, Radim Krčmář wrote: 2017-07-03 17:28+0800, Yang Zhang: The background is that we(Alibaba Cloud) do get more and more complaints from our customers in both KVM and Xen compare to bare-mental.After investigations, the root cause is known

Re: [RFC PATCH v2 0/7] x86/idle: add halt poll support

On 08/29/2017 01:46 PM, Yang Zhang wrote: Some latency-intensive workload will see obviously performance drop when running inside VM. The main reason is that the overhead is amplified when running inside VM. The most cost i have seen is inside idle path. This patch introduces a new mechanism to