From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juan Quintela <quintela@redhat.com>
Subject: Re: [QEMU PATCH v2] kvmclock: advance clock by time window between vm_stop and pre_save
Date: Fri, 04 Nov 2016 19:57:59 +0100
Message-ID: <8760o3nkco.fsf@emacs.mitica>
References: <20161104094322.GA16930@amt.cnet> <20161104165933.GA3027@amt.cnet>
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Cc: kvm@vger.kernel.org, qemu-devel <qemu-devel@nongnu.org>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Eduardo Habkost <ehabkost@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
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In-Reply-To: <20161104165933.GA3027@amt.cnet> (Marcelo Tosatti's message of
        "Fri, 4 Nov 2016 14:59:36 -0200")
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Marcelo Tosatti <mtosatti@redhat.com> wrote:
> This patch, relative to pre-copy migration codepath,
> measures the time between vm_stop() and pre_save(),
> which includes copying the remaining RAM to destination,
> and advances the clock by that amount.
>
> In a VM with 5 seconds downtime, this reduces the guest
> clock difference on destination from 5s to 0.2s.
>
> Tested with Linux and Windows 2012 R2 guests with -cpu XXX,+hv-time.
>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
> ---
>
> v2: use subsection (Juan Quintela)
>     fix older machine types support
>

Reviewed-by: Juan Quintela <quintela@redhat.com>