From: Marcelo Tosatti <mtosatti@redhat.com>
To: Gleb Natapov <gleb@redhat.com>
Cc: "Joji Mekkattuparamban (joji)" <joji@cisco.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
kvm@vger.kernel.org
Subject: Re: [Qemu-devel] Para-Virtualized Clock Usage
Date: Wed, 24 Apr 2013 05:27:48 -0300 [thread overview]
Message-ID: <20130424082748.GA14374@amt.cnet> (raw)
In-Reply-To: <20130423055215.GA12401@redhat.com>
On Tue, Apr 23, 2013 at 08:52:16AM +0300, Gleb Natapov wrote:
> On Mon, Apr 22, 2013 at 04:58:01PM +0000, Joji Mekkattuparamban (joji) wrote:
> > Greetings,
> >
> > I have a SMP guest application, running on the 2.6.27 Linux kernel. The application, originally written for bare metal, makes extensive use of the TSC, by directly invoking rdtsc from the user space for timestamp purposes. While running on KVM (RHEL version 6.3), we are running into TSC issues on some hardware. As a solution, I am considering migrating to the pvclock. I am wondering if there is an example for migrating from TSC to the pvclock. Any pointers?
> >
> Wrong list, you should ask KVM (copied). Recent kernels have pvclock
> vdso support which means that gettimeofday() uses it without entering
> the kernel. Marcelo?
>
> --
> Gleb.
Converting application to make use of gettimeofday() should be the
best way to make use of pvclock, yes.
next prev parent reply other threads:[~2013-04-24 21:59 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-22 16:58 [Qemu-devel] Para-Virtualized Clock Usage Joji Mekkattuparamban (joji)
2013-04-23 5:52 ` Gleb Natapov
2013-04-24 8:27 ` Marcelo Tosatti [this message]
2013-04-25 0:28 ` Joji Mekkattuparamban (joji)
2013-04-25 6:57 ` Gleb Natapov
2013-05-15 20:40 ` Joji Mekkattuparamban (joji)
2013-05-16 8:37 ` Gleb Natapov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20130424082748.GA14374@amt.cnet \
--to=mtosatti@redhat.com \
--cc=gleb@redhat.com \
--cc=joji@cisco.com \
--cc=kvm@vger.kernel.org \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).