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Subject: Re: [PATCH] KVM: LAPIC: Periodically revaluate appropriate
 lapic_timer_advance_ns
To:     Wanpeng Li <kernellwp@gmail.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Fri, 9 Aug 2019 12:24:08 +0200
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On 09/08/19 07:45, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@tencent.com>
> 
> Even if for realtime CPUs, cache line bounces, frequency scaling, presence 
> of higher-priority RT tasks, etc can cause different response. These 
> interferences should be considered and periodically revaluate whether 
> or not the lapic_timer_advance_ns value is the best, do nothing if it is,
> otherwise recaluate again. 

How much fluctuation do you observe between different runs?

Paolo