Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 24 Jul 2010 11:58:56 -0500
From:      Alan Cox <alan.l.cox@gmail.com>
To:        Alexander Motin <mav@freebsd.org>
Cc:        freebsd-hackers@freebsd.org, freebsd-performance@freebsd.org
Subject:   Re: Intel TurboBoost in practice
Message-ID:  <AANLkTi=XFBOc30zNjC-DOCtxsHUnozvDX4ABMJ_354Re@mail.gmail.com>
In-Reply-To: <4C4AF046.40507@FreeBSD.org>
References:  <4C4AF046.40507@FreeBSD.org>

next in thread | previous in thread | raw e-mail | index | archive | help
2010/7/24 Alexander Motin <mav@freebsd.org>

> Hi.
>
> I've make small observations of Intel TurboBoost technology under
> FreeBSD. This technology allows Intel Core i5/i7 CPUs to rise frequency
> of some cores if other cores are idle and power/thermal conditions
> permit. CPU core counted as idle, if it has been put into C3 or deeper
> power state (may reflect ACPI C2/C3 states). So to reach maximal
> effectiveness, some tuning may be needed.
>
>
[snip]


>
> PPS: I expect even better effect achieved by further reducing interrupt
> rates on idle CPUs.
>
>
I'm currently testing a patch that eliminates another 31% of the global TLB
shootdowns for a "buildworld" on an amd64 machine.  So, you can expect
improvement in this area.

Alan



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?AANLkTi=XFBOc30zNjC-DOCtxsHUnozvDX4ABMJ_354Re>