Date: Mon, 26 Jul 2010 13:19:36 +0100 (BST) From: Robert Watson <rwatson@FreeBSD.org> To: Alexander Motin <mav@FreeBSD.org> Cc: freebsd-hackers@freebsd.org, freebsd-performance@freebsd.org, Rui Paulo <rpaulo@lavabit.com> Subject: Re: Intel TurboBoost in practice Message-ID: <alpine.BSF.2.00.1007261318380.10170@fledge.watson.org> In-Reply-To: <4C4B720A.6020802@FreeBSD.org> References: <4C4AF046.40507@FreeBSD.org> <A30A636F-E925-456E-8866-4E46B3BA367F@lavabit.com> <4C4B720A.6020802@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, 25 Jul 2010, Alexander Motin wrote: >> The numbers that you are showing doesn't show much difference. Have you >> tried buildworld? > > If you mean relative difference -- as I have told, it's mostly because of my > CPU. It's maximal boost is 266MHz (8.3%), but 133MHz of them is enabled most > of time if CPU is not overheated. It probably doesn't, as it works on clear > table under air conditioner. So maximal effect I can expect on is 4.2%. In > such situation 2.8% probably not so bad to illustrate that feature works and > there is space for further improvements. If I had Core i5-750S I would > expect 33% boost. Can I recommend the use of ministat(1) and sample sizes of at least 8 runs per configuration? Robert > > If you mean absolute difference, here are results or four buildworld runs: > hw.acpi.cpu.cx_lowest=C1: 4654.23 sec > hw.acpi.cpu.cx_lowest=C2: 4556.37 sec > hw.acpi.cpu.cx_lowest=C2: 4570.85 sec > hw.acpi.cpu.cx_lowest=C1: 4679.83 sec > Benefit is about 2.1%. Each time results were erased and sources > pre-cached into RAM. Storage was SSD, so disk should not be an issue. > > -- > Alexander Motin > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.BSF.2.00.1007261318380.10170>