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Date: Thu, 26 May 2016 13:33:31 -0700
From: yunhong jiang <yunhong.jiang@linux.intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, Wanpeng Li <wanpeng.li@hotmail.com>,
        Radim =?UTF-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        David Matlack <dmatlack@google.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Yang Zhang <yang.zhang.wz@gmail.com>
Subject: Re: [PATCH v5] KVM: halt-polling: poll for the upcoming fire timers
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On Thu, 26 May 2016 12:26:27 +0200
Paolo Bonzini <pbonzini@redhat.com> wrote:

> 
> 
> On 25/05/2016 04:47, Wanpeng Li wrote:
> > From: Wanpeng Li <wanpeng.li@hotmail.com>
> > 
> > If an emulated lapic timer will fire soon(in the scope of 10us the
> > base of dynamic halt-polling, lower-end of message passing workload
> > latency TCP_RR's poll time < 10us) we can treat it as a short halt,
> > and poll to wait it fire, the fire callback apic_timer_fn() will set
> > KVM_REQ_PENDING_TIMER, and this flag will be check during busy poll.
> > This can avoid context switch overhead and the latency which we wake
> > up vCPU.
> 
> As discussed on IRC, I would like to understand why the adaptive

Glad to know the IRC channel. Is #kvm channel on freenode the IRC you are
talking about?

Thanks
--jyh