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Date:      Thu, 15 Apr 2010 13:28:34 +0900 (JST)
From:      Maho NAKATA <chat95@mac.com>
To:        smithi@nimnet.asn.au
Cc:        amvandemore@gmail.com, freebsd-stable@freebsd.org, alc@freebsd.org, alan.l.cox@gmail.com, avg@freebsd.org, yanefbsd@gmail.com, als@modulus.org
Subject:   Re: HyperThreading makes worse to me
Message-ID:  <20100415.132834.229420430668646074.chat95@mac.com>
In-Reply-To: <20100415135034.J52200@sola.nimnet.asn.au>
References:  <n2i7d6fde3d1004141949z2689a81cwf8c48805ea09d68@mail.gmail.com> <k2x7d6fde3d1004141950t81b4214awddea4563182526c5@mail.gmail.com> <20100415135034.J52200@sola.nimnet.asn.au>

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From: Ian Smith <smithi@nimnet.asn.au>
Subject: Re: HyperThreading makes worse to me (was Re: How to reproduce=
: Re: Only 70% of theoretical peak performance on FreeBSD 8/amd64, Core=
i7 920)
Date: Thu, 15 Apr 2010 14:21:30 +1000 (EST)

> Er, shouldn't one of those say HTT on?  and/or Turbo boost on?  Else =

> they're both the same test as [4] but with different results?
sorry,

Turbo Boost off, Hyper threading off: 82% (35GFlops) =A0 =A0[1]
Turbo Boost off, Hyper threading on: 72% (30.5GFlops) =A0[2]

HTT on performs always worse.

> Clarification of all four possible test configs - 8 if you add pinnin=
g =

> CPUs or not - might make this a bit clearer?
right. Pinning might not be so important I guess. Core i7 is not NUMA.

Thanks,
-- Nakata Maho http://accc.riken.jp/maho/ , JA OOO http://ja.openoffice=
.org/
   Blog: http://blog.goo.ne.jp/nakatamaho/ , GPG key: http://accc.riken=
.jp/maho/maho.pgp.txt



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