From: Blue Swirl <blauwirbel@gmail.com>
To: Glauber Costa <glommer@redhat.com>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] re-set rtc date on reset handler
Date: Tue, 1 Sep 2009 19:56:56 +0300 [thread overview]
Message-ID: <f43fc5580909010956l5f4b8ea1p47bf85811a4f858a@mail.gmail.com> (raw)
In-Reply-To: <1251822154-5423-1-git-send-email-glommer@redhat.com>
On Tue, Sep 1, 2009 at 7:22 PM, Glauber Costa<glommer@redhat.com> wrote:
> guests without a stable timesource such as kvm-clock will grab the wallclock
> from our rtc chip. However, we only sync the date when we first launch qemu.
> If a guest goes through a series of reboot cycles, it will slowly see time
> getting far behind the host.
>
> The proposal of this patch is to set the date to host clock again in the reset
> handler. With this patch, I see a Fedora guest keeping its clock in sync upon
> an ulimited number of reboots.
A different approach is used in m48t59.c: the guest clock is generated
directly from host clock without any timers and only a fixed offset
(to account for time when guest was stopped) is added, so the clock
will always in sync.
next prev parent reply other threads:[~2009-09-01 16:57 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-01 16:22 [Qemu-devel] [PATCH] re-set rtc date on reset handler Glauber Costa
2009-09-01 16:56 ` Blue Swirl [this message]
2009-09-01 23:00 ` Glauber Costa
2009-09-08 14:55 ` Dor Laor
2009-09-08 16:15 ` [Qemu-devel] " Jan Kiszka
2009-09-08 16:50 ` Jan Kiszka
2009-09-08 17:00 ` Jan Kiszka
2009-09-09 12:28 ` Dor Laor
2009-09-09 12:57 ` Jan Kiszka
2009-09-09 13:27 ` Avi Kivity
2009-09-09 13:31 ` Jan Kiszka
2009-09-09 15:04 ` Avi Kivity
2009-09-09 15:34 ` Anthony Liguori
2009-09-09 16:09 ` Gleb Natapov
2009-09-09 17:52 ` Anthony Liguori
2009-09-09 18:40 ` Gleb Natapov
2009-09-09 18:50 ` Anthony Liguori
2009-09-09 18:25 ` Avi Kivity
2009-09-09 18:33 ` Anthony Liguori
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