From: Joel Schopp <jschopp@austin.ibm.com>
To: Gabriel Paubert <paubert@iram.es>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
linuxppc-dev@lists.ozlabs.org,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
ego@in.ibm.com
Subject: Re: [PATCHv3 2/2] powerpc: implement arch_scale_smt_power for Power7
Date: Fri, 29 Jan 2010 10:26:15 -0600 [thread overview]
Message-ID: <4B630C27.1060405@austin.ibm.com> (raw)
In-Reply-To: <20100129122536.GA11156@iram.es>
Gabriel Paubert wrote:
> On Thu, Jan 28, 2010 at 05:20:55PM -0600, Joel Schopp wrote:
>
>> On Power7 processors running in SMT4 mode with 2, 3, or 4 idle threads
>> there is performance benefit to idling the higher numbered threads in
>> the core.
>>
>>
>
> Really 2, 3, or 4? When you have 4 idle threads out of 4, performance
> becomes a minor concern, no? ;-)
>
> Gabriel
>
Yes, but going from 4 idle to 3 idle you want to keep the slanted
weights. If you ignored 4 you'd place wrong and then correct it after
the fact.
WARNING: multiple messages have this Message-ID (diff)
From: Joel Schopp <jschopp@austin.ibm.com>
To: Gabriel Paubert <paubert@iram.es>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
ego@in.ibm.com, linux-kernel@vger.kernel.org,
Ingo Molnar <mingo@elte.hu>,
linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCHv3 2/2] powerpc: implement arch_scale_smt_power for Power7
Date: Fri, 29 Jan 2010 10:26:15 -0600 [thread overview]
Message-ID: <4B630C27.1060405@austin.ibm.com> (raw)
In-Reply-To: <20100129122536.GA11156@iram.es>
Gabriel Paubert wrote:
> On Thu, Jan 28, 2010 at 05:20:55PM -0600, Joel Schopp wrote:
>
>> On Power7 processors running in SMT4 mode with 2, 3, or 4 idle threads
>> there is performance benefit to idling the higher numbered threads in
>> the core.
>>
>>
>
> Really 2, 3, or 4? When you have 4 idle threads out of 4, performance
> becomes a minor concern, no? ;-)
>
> Gabriel
>
Yes, but going from 4 idle to 3 idle you want to keep the slanted
weights. If you ignored 4 you'd place wrong and then correct it after
the fact.
next prev parent reply other threads:[~2010-01-29 16:26 UTC|newest]
Thread overview: 103+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-20 20:00 [PATCH 0/2] sched: arch_scale_smt_powers Joel Schopp
2010-01-20 20:00 ` Joel Schopp
2010-01-20 20:02 ` [PATCH 1/2] sched: Fix the place where group powers are updated Joel Schopp
2010-01-20 20:02 ` Joel Schopp
2010-01-21 13:54 ` [tip:sched/core] " tip-bot for Gautham R Shenoy
2010-01-26 23:28 ` [PATCHv2 1/2] sched: enable ARCH_POWER Joel Schopp
2010-01-26 23:28 ` Joel Schopp
2010-01-28 23:20 ` [PATCHv3 " Joel Schopp
2010-01-28 23:20 ` Joel Schopp
2010-02-05 20:57 ` [PATCHv4 " Joel Schopp
2010-02-05 20:57 ` Joel Schopp
2010-01-20 20:04 ` [PATCH 2/2] powerpc: implement arch_scale_smt_power for Power7 Joel Schopp
2010-01-20 20:04 ` Joel Schopp
2010-01-20 20:48 ` Peter Zijlstra
2010-01-20 20:48 ` Peter Zijlstra
2010-01-20 21:58 ` Michael Neuling
2010-01-20 21:58 ` Michael Neuling
2010-01-20 22:44 ` Joel Schopp
2010-01-20 22:44 ` Joel Schopp
2010-01-21 8:27 ` Peter Zijlstra
2010-01-21 8:27 ` Peter Zijlstra
2010-01-20 21:04 ` Michael Neuling
2010-01-20 21:04 ` Michael Neuling
2010-01-20 22:09 ` Joel Schopp
2010-01-20 22:09 ` Joel Schopp
2010-01-24 3:00 ` Benjamin Herrenschmidt
2010-01-24 3:00 ` Benjamin Herrenschmidt
2010-01-25 17:50 ` Joel Schopp
2010-01-25 17:50 ` Joel Schopp
2010-01-26 4:23 ` Benjamin Herrenschmidt
2010-01-26 4:23 ` Benjamin Herrenschmidt
2010-01-20 21:33 ` Benjamin Herrenschmidt
2010-01-20 21:33 ` Benjamin Herrenschmidt
2010-01-20 22:36 ` Joel Schopp
2010-01-20 22:36 ` Joel Schopp
2010-01-26 23:28 ` [PATCHv2 " Joel Schopp
2010-01-26 23:28 ` Joel Schopp
2010-01-27 0:52 ` Benjamin Herrenschmidt
2010-01-27 0:52 ` Benjamin Herrenschmidt
2010-01-28 22:39 ` Joel Schopp
2010-01-28 22:39 ` Joel Schopp
2010-01-29 1:23 ` Benjamin Herrenschmidt
2010-01-29 1:23 ` Benjamin Herrenschmidt
2010-01-28 23:20 ` [PATCHv3 " Joel Schopp
2010-01-28 23:20 ` Joel Schopp
2010-01-28 23:24 ` Joel Schopp
2010-01-28 23:24 ` Joel Schopp
2010-01-29 1:23 ` Benjamin Herrenschmidt
2010-01-29 1:23 ` Benjamin Herrenschmidt
2010-01-29 10:13 ` Peter Zijlstra
2010-01-29 10:13 ` Peter Zijlstra
2010-01-29 18:34 ` Joel Schopp
2010-01-29 18:34 ` Joel Schopp
2010-01-29 18:41 ` Joel Schopp
2010-01-29 18:41 ` Joel Schopp
2010-02-05 20:57 ` [PATCHv4 " Joel Schopp
2010-02-05 20:57 ` Joel Schopp
2010-02-14 10:12 ` Peter Zijlstra
2010-02-14 10:12 ` Peter Zijlstra
2010-02-17 22:20 ` Michael Neuling
2010-02-17 22:20 ` Michael Neuling
2010-02-18 13:17 ` Peter Zijlstra
2010-02-18 13:17 ` Peter Zijlstra
2010-02-18 13:19 ` Peter Zijlstra
2010-02-18 13:19 ` Peter Zijlstra
2010-02-18 16:28 ` Joel Schopp
2010-02-18 16:28 ` Joel Schopp
2010-02-18 17:08 ` Peter Zijlstra
2010-02-18 17:08 ` Peter Zijlstra
2010-02-19 6:05 ` Michael Neuling
2010-02-19 6:05 ` Michael Neuling
2010-02-19 10:01 ` Peter Zijlstra
2010-02-19 10:01 ` Peter Zijlstra
2010-02-19 11:01 ` Michael Neuling
2010-02-19 11:01 ` Michael Neuling
2010-02-23 6:08 ` Michael Neuling
2010-02-23 6:08 ` Michael Neuling
2010-02-23 16:24 ` Peter Zijlstra
2010-02-23 16:24 ` Peter Zijlstra
2010-02-23 16:30 ` Peter Zijlstra
2010-02-23 16:30 ` Peter Zijlstra
2010-02-24 6:07 ` Michael Neuling
2010-02-24 6:07 ` Michael Neuling
2010-02-24 11:13 ` Michael Neuling
2010-02-24 11:13 ` Michael Neuling
2010-02-24 11:58 ` Michael Neuling
2010-02-24 11:58 ` Michael Neuling
2010-02-27 10:21 ` Michael Neuling
2010-02-27 10:21 ` Michael Neuling
2010-03-02 14:44 ` Peter Zijlstra
2010-03-02 14:44 ` Peter Zijlstra
2010-03-04 22:28 ` Michael Neuling
2010-03-04 22:28 ` Michael Neuling
2010-01-29 12:25 ` [PATCHv3 " Gabriel Paubert
2010-01-29 12:25 ` Gabriel Paubert
2010-01-29 16:26 ` Joel Schopp [this message]
2010-01-29 16:26 ` Joel Schopp
2010-01-26 23:27 ` [PATCHv2 0/2] sched: arch_scale_smt_powers v2 Joel Schopp
2010-01-26 23:27 ` Joel Schopp
2010-01-28 23:20 ` [PATCHv3 0/2] sched: arch_scale_smt_powers Joel Schopp
2010-01-28 23:20 ` Joel Schopp
2010-02-05 20:57 ` [PATCHv4 " Joel Schopp
2010-02-05 20:57 ` Joel Schopp
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=4B630C27.1060405@austin.ibm.com \
--to=jschopp@austin.ibm.com \
--cc=a.p.zijlstra@chello.nl \
--cc=ego@in.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mingo@elte.hu \
--cc=paubert@iram.es \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.