From: "H. Peter Anvin" <hpa@zytor.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>,
Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
"Luck, Tony" <tony.luck@intel.com>,
Steven Rostedt <rostedt@goodmis.org>,
Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@elte.hu>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Thomas Gleixner <tglx@linutronix.de>,
David Miller <davem@davemloft.net>,
Ingo Molnar <mingo@redhat.com>
Subject: Re: [RFC patch 15/15] LTTng timestamp x86
Date: Mon, 20 Oct 2008 15:29:07 -0700 [thread overview]
Message-ID: <48FD0633.70604@zytor.com> (raw)
In-Reply-To: <alpine.LFD.2.00.0810201451190.3287@nehalem.linux-foundation.org>
Linus Torvalds wrote:
>
> But it's not going to solve the "hey, I have 512 CPU's, they are all on
> different boards, and no, they are _not_ synchronized to one global
> clock!".
>
> That's why I'd suggest making _purely_ local time, and then aiming for
> something NTP-like. But maybe there are better solutions out there.
>
At the same time, it would definitely be nice to encourage vendors of
large SMP systems to provide a common root crystal (frequency standard)
for a single SMP domain. Preferrably a really good one, TCXO or better.
-hpa
next prev parent reply other threads:[~2008-10-20 22:29 UTC|newest]
Thread overview: 94+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-16 23:27 [RFC patch 00/15] Tracer Timestamping Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 01/15] get_cycles() : kconfig HAVE_GET_CYCLES Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 02/15] get_cycles() : x86 HAVE_GET_CYCLES Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 03/15] get_cycles() : sparc64 HAVE_GET_CYCLES Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-17 2:48 ` [RFC patch 03/15] get_cycles() : sparc64 HAVE_GET_CYCLES (update) Mathieu Desnoyers
2008-10-17 2:48 ` Mathieu Desnoyers
2008-10-17 2:57 ` David Miller
2008-10-16 23:27 ` [RFC patch 04/15] get_cycles() : powerpc64 HAVE_GET_CYCLES Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-17 0:26 ` Paul Mackerras
2008-10-17 0:43 ` [RFC patch 04/15] get_cycles() : powerpc64 HAVE_GET_CYCLES (update) Mathieu Desnoyers
2008-10-17 0:43 ` Mathieu Desnoyers
2008-10-17 0:54 ` Paul Mackerras
2008-10-17 1:42 ` David Miller
2008-10-17 2:08 ` Mathieu Desnoyers
2008-10-17 2:08 ` Mathieu Desnoyers
2008-10-17 2:33 ` David Miller
2008-10-16 23:27 ` [RFC patch 05/15] get_cycles() : MIPS HAVE_GET_CYCLES_32 Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-26 10:18 ` Ralf Baechle
2008-10-26 10:18 ` Ralf Baechle
2008-10-26 20:39 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 06/15] LTTng build Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-17 8:10 ` KOSAKI Motohiro
2008-10-17 16:18 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 07/15] LTTng timestamp Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-17 8:15 ` KOSAKI Motohiro
2008-10-17 16:23 ` Mathieu Desnoyers
2008-10-17 16:23 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 08/15] LTTng - Timestamping Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 09/15] LTTng mips export hpt frequency Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 10/15] LTTng timestamp mips Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 11/15] LTTng timestamp powerpc Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 12/15] LTTng timestamp sparc64 Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 13/15] LTTng timestamp sh Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 14/15] LTTng - TSC synchronicity test Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-16 23:27 ` [RFC patch 15/15] LTTng timestamp x86 Mathieu Desnoyers
2008-10-16 23:27 ` Mathieu Desnoyers
2008-10-17 0:08 ` Linus Torvalds
2008-10-17 0:12 ` Linus Torvalds
2008-10-17 1:28 ` Mathieu Desnoyers
2008-10-17 2:19 ` Luck, Tony
2008-10-17 2:19 ` Luck, Tony
2008-10-17 17:25 ` Steven Rostedt
2008-10-17 18:08 ` Luck, Tony
2008-10-17 18:42 ` Mathieu Desnoyers
2008-10-17 18:58 ` Luck, Tony
2008-10-17 20:23 ` Mathieu Desnoyers
2008-10-17 23:52 ` Luck, Tony
2008-10-18 17:01 ` Mathieu Desnoyers
2008-10-18 17:01 ` Mathieu Desnoyers
2008-10-18 17:35 ` Linus Torvalds
2008-10-18 17:50 ` Ingo Molnar
2008-10-22 16:19 ` Mathieu Desnoyers
2008-10-22 15:53 ` Mathieu Desnoyers
2008-10-20 18:07 ` Luck, Tony
2008-10-22 16:51 ` Mathieu Desnoyers
2008-10-17 19:17 ` Steven Rostedt
2008-10-20 20:10 ` Linus Torvalds
2008-10-20 20:10 ` Linus Torvalds
2008-10-20 21:38 ` john stultz
2008-10-20 22:06 ` Linus Torvalds
2008-10-20 22:17 ` Ingo Molnar
2008-10-20 22:17 ` Ingo Molnar
2008-10-20 22:29 ` H. Peter Anvin [this message]
2008-10-20 22:29 ` H. Peter Anvin
2008-10-21 18:10 ` Bjorn Helgaas
2008-10-23 15:47 ` Linus Torvalds
2008-10-23 16:39 ` H. Peter Anvin
2008-10-23 21:54 ` Paul Mackerras
2008-10-20 23:47 ` john stultz
2008-10-20 23:47 ` john stultz
2008-10-22 17:05 ` Mathieu Desnoyers
2008-10-17 19:36 ` Christoph Lameter
2008-10-17 7:59 ` [RFC patch 00/15] Tracer Timestamping Peter Zijlstra
2008-10-20 20:25 ` Mathieu Desnoyers
2008-10-20 20:25 ` Mathieu Desnoyers
2008-10-21 0:20 ` Nicolas Pitre
2008-10-21 1:32 ` Mathieu Desnoyers
2008-10-21 2:32 ` Nicolas Pitre
2008-10-21 4:05 ` Mathieu Desnoyers
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=48FD0633.70604@zytor.com \
--to=hpa@zytor.com \
--cc=a.p.zijlstra@chello.nl \
--cc=akpm@linux-foundation.org \
--cc=davem@davemloft.net \
--cc=johnstul@us.ibm.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mathieu.desnoyers@polymtl.ca \
--cc=mingo@elte.hu \
--cc=mingo@redhat.com \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=torvalds@linux-foundation.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).