From: Paolo Bonzini <pbonzini@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
mingo@redhat.com, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [patch 3/3] x86: kvm guest side support for KVM_HC_RT_PRIO hypercall\
Date: Thu, 28 Sep 2017 09:22:02 +0200 [thread overview]
Message-ID: <10635834-459a-9ec1-624d-febd6b5af243@redhat.com> (raw)
In-Reply-To: <20170928004452.GA30040@amt.cnet>
On 28/09/2017 02:44, Marcelo Tosatti wrote:
>> Again: if you have many interruptions, it's not a flaw in KVM or QEMU's
>> design, it's just that someone is doing something stupid. It could be
>> the guest (e.g. unnecessary devices or daemons as in the example above),
>> QEMU (e.g. the RTC emulation used to trigger QEMU timers twice a second
>> just to increment the clock), or the management (e.g. polling "is the VM
>> running" 50 times per second). But it can and must be fixed.
>
> No, i mean you can run anything in VCPU-0 (it is valid to do that).
> And that "anything" can generate 1 interrupt per second, 1000 or 10.000
> interrupts per second. Which are all valid things to be done.
>
> "I can't run a kernel compilation on VCPU-0 because that will impact
> latency on the realtime VCPU-1" is not acceptable.
That shouldn't happen. Sources of frequent interruptions have all been
fixed or moved outside the main thread.
If there are more left, report the bug and we'll see how to fix it in
userspace.
Paolo
next prev parent reply other threads:[~2017-09-28 7:22 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-21 11:38 [patch 0/3] KVM KVM_HC_RT_PRIO hypercall support Marcelo Tosatti
2017-09-21 11:38 ` [patch 1/3] KVM: x86: add per-vcpu option to set guest vcpu -RT priority Marcelo Tosatti
2017-09-21 11:38 ` [patch 2/3] KVM: x86: KVM_HC_RT_PRIO hypercall (host-side) Marcelo Tosatti
2017-09-21 13:32 ` Konrad Rzeszutek Wilk
2017-09-21 13:49 ` Paolo Bonzini
2017-09-22 1:08 ` Marcelo Tosatti
2017-09-22 7:23 ` Paolo Bonzini
2017-09-22 12:24 ` Marcelo Tosatti
2017-09-21 11:38 ` [patch 3/3] x86: kvm guest side support for KVM_HC_RT_PRIO hypercall Marcelo Tosatti
2017-09-21 13:36 ` Konrad Rzeszutek Wilk
2017-09-21 14:06 ` Peter Zijlstra
2017-09-22 1:10 ` Marcelo Tosatti
2017-09-22 10:00 ` Peter Zijlstra
2017-09-22 10:56 ` Peter Zijlstra
2017-09-22 12:33 ` Marcelo Tosatti
2017-09-22 12:55 ` Peter Zijlstra
2017-09-23 10:56 ` Paolo Bonzini
2017-09-23 13:41 ` Peter Zijlstra
2017-09-24 13:05 ` Paolo Bonzini
2017-09-25 2:57 ` Marcelo Tosatti
2017-09-25 9:13 ` Peter Zijlstra
2017-09-25 15:12 ` Paolo Bonzini
2017-09-26 22:49 ` [patch 3/3] x86: kvm guest side support for KVM_HC_RT_PRIO hypercall\ Marcelo Tosatti
2017-09-27 9:37 ` Paolo Bonzini
2017-09-28 0:44 ` Marcelo Tosatti
2017-09-28 7:22 ` Paolo Bonzini [this message]
2017-09-28 21:35 ` Marcelo Tosatti
2017-09-28 21:41 ` Marcelo Tosatti
2017-09-29 8:18 ` Paolo Bonzini
2017-09-29 16:40 ` Marcelo Tosatti
2017-09-29 17:05 ` Paolo Bonzini
2017-09-29 20:17 ` Marcelo Tosatti
2017-10-02 12:30 ` Paolo Bonzini
2017-10-02 12:48 ` Peter Zijlstra
2017-09-26 23:22 ` [patch 3/3] x86: kvm guest side support for KVM_HC_RT_PRIO hypercall Marcelo Tosatti
2017-09-25 16:20 ` Konrad Rzeszutek Wilk
2017-09-22 12:16 ` Marcelo Tosatti
2017-09-22 12:31 ` Peter Zijlstra
2017-09-22 12:36 ` Marcelo Tosatti
2017-09-22 12:59 ` Peter Zijlstra
2017-09-25 1:52 ` Marcelo Tosatti
2017-09-25 8:35 ` Peter Zijlstra
2017-09-22 12:40 ` [patch 3/3] x86: kvm guest side support for KVM_HC_RT_PRIO hypercall\ Marcelo Tosatti
2017-09-22 13:01 ` Peter Zijlstra
2017-09-25 2:22 ` Marcelo Tosatti
2017-09-25 8:58 ` Peter Zijlstra
2017-09-25 10:41 ` Thomas Gleixner
2017-09-25 18:28 ` Jan Kiszka
2017-09-21 17:45 ` [patch 0/3] KVM KVM_HC_RT_PRIO hypercall support Jan Kiszka
2017-09-22 1:19 ` Marcelo Tosatti
2017-09-22 6:23 ` Jan Kiszka
2017-09-26 23:59 ` Marcelo Tosatti
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