From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADB0BC433DB for ; Thu, 25 Mar 2021 20:56:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 796FC61A3C for ; Thu, 25 Mar 2021 20:56:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230009AbhCYU4O (ORCPT ); Thu, 25 Mar 2021 16:56:14 -0400 Received: from mx2.suse.de ([195.135.220.15]:39230 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229930AbhCYUzp (ORCPT ); Thu, 25 Mar 2021 16:55:45 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1616705743; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3VfPe5ytwFivyYXwTXxlEptQEfs03cyz3RRJOvqsjuc=; b=Z+JklyVVt0g/gvaMqT0bswxymztMmmgwhTbS35JrycakhdYNmVkc/trzREcVDeeGxp3lTH lBRv5/oM8MGkYRzuZqW0v1ObfexR62YhYJSH2rqZVNk6Nim2XI5kVOsuzO499ZssG9vi8d /k/273RCPYAguov397/hm6Lc6y89oko= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 89A37ACBF; Thu, 25 Mar 2021 20:55:43 +0000 (UTC) Message-ID: <3871a1520068e44bf339e430bef2fcf55cbc1cdb.camel@suse.com> Subject: Re: [PATCH v32 0/5]Timestamp synchronization of host - guest tracing session From: Dario Faggioli To: Steven Rostedt , Tzvetomir Stoyanov Cc: Stefano De Venuto , Linux Trace Devel Date: Thu, 25 Mar 2021 21:55:42 +0100 In-Reply-To: <20210322105624.40aa27b1@gandalf.local.home> References: <20210315061857.168570-1-tz.stoyanov@gmail.com> <6796a75b-6a59-767f-08ec-ee0cbfd8c825@gmail.com> <80486620-fe8f-49a5-cdac-05bb2b969984@gmail.com> <0f6e158c-43a3-4117-2a17-5a13cd6a7970@gmail.com> <20210322105624.40aa27b1@gandalf.local.home> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-ksnTe6fXwiUUM+MAro5X" User-Agent: Evolution 3.38.4 (by Flathub.org) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org --=-ksnTe6fXwiUUM+MAro5X Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2021-03-22 at 10:56 -0400, Steven Rostedt wrote: > On Mon, 22 Mar 2021 12:13:09 +0200 > Tzvetomir Stoyanov wrote: >=20 > > Confirmed, the problem is in the trace-cmd logic that works with > > the > > KVM scaling.=C2=A0 Looks like tsc-scaling-ratio is the default KVM > > scaling > > on your machine, (1 << 32), and in that case the scaling should be > > ignored in our calculations. I still have no solution, going to > > analyze how the KVM scaling works. >=20 > I'm guessing that this was run on a AMD CPU, as the default scaling > (the > one to ignore) is 1 << 32 for AMD and for Intel it's 1 << 48. >=20 BTW, yes. Stefano could give us details (lscpu or anything) if necessary, but this indeed is AMD. Regards --=20 Dario Faggioli, Ph.D http://about.me/dario.faggioli Virtualization Software Engineer SUSE Labs, SUSE https://www.suse.com/ ------------------------------------------------------------------- <> (Raistlin Majere) --=-ksnTe6fXwiUUM+MAro5X Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEES5ssOj3Vhr0WPnOLFkJ4iaW4c+4FAmBc+M4ACgkQFkJ4iaW4 c+6Q8xAAunJYCrjkrOcmowcErYupDVCi2jCGVSC643g2A4ZK60VpNdL83JZjhgHt h29jSD9QK26q0JFpK/W67dCWEawfYjjPbyU2DtYNMZS4NNuz7oNk53SAyLSqwl2B z1h6uR1wkYdZfvXI2hO68kummPWW9jl/Ys6VHh0eAQGx8o9xDmzMlBqL3wXu8dmQ T3X5h8WmvAqRtzQfh55NpP8Ek1d5bPzum9VrXUOn0iL9nsrQqf0Te9B7/bjV0CVv XwaE66en8YTlDisvxLeEpeZcoVMaoSg80XZh1I51zpNB2F9YU/kxEzQwwh1klsfK klR9lpiShmX1LwXDiw8JY0VrCL6oy8agB3zMncGM65I6soAnoxdDWqdvzf5vBQN2 5KxlBlU3OeTOvAro0bZl1udANirYEA8R4VFZbNB6fv8L+IMXDQdA14MvUmxy0JtZ 3xdYCHu/BMUODLtSXopL7X8CBMXS71ZgxFVU6Porb7OF+VWjCN2YIiBSAQMl1s0C NCqHfBFrU8I0i4smRdNob5qG1esjZPTYteh1Mz7D2pClA6p5mB7sDBMRMa/atMmg qY1wOUUpkMVsH7T6/0IOII5T0t6Tf96u9Sl9sGzmOe09z4k/iKtRK+o+wu0TATel lQVcxymk5YJlPwJpyCEbWLhQ6LbxDbBXj1JPQUiVOOvr8+j6M5Y= =3Gpy -----END PGP SIGNATURE----- --=-ksnTe6fXwiUUM+MAro5X--