Date: Tue, 21 Feb 2012 04:27:23 +0900 From: Nathan Whitehorn <nwhitehorn@freebsd.org> To: Super Bisquit <superbisquit@gmail.com> Cc: "Kevin H. Patterson" <kpatterson.home@gmail.com>, FreeBSD PowerPC ML <freebsd-ppc@freebsd.org> Subject: Re: FreeBSD 9.0-RELEASE on PowerMac Dual G5 Message-ID: <4F429E9B.4040500@freebsd.org> In-Reply-To: <CA%2BWntOsjc6X329ujtxwgJP1=JceVu__=khntX9F2cVokKZq6eg@mail.gmail.com> References: <3934AD65-E01C-4DDD-8BDC-F52C6AE3655F@khptech.com> <CA%2BWntOtKvc6HMDoMNQj6AQtiA5kOXGrZqcnFcssuGs6nv_EimQ@mail.gmail.com> <4D7B47E5-6A33-4426-8186-D5E9D5C9B32E@khptech.com> <CA%2BWntOsYiKaygJBg_iQBkZ9YX1JjGF0_MnbzJwHqOxyK2uBnYg@mail.gmail.com> <8830CCB0-1417-4678-A766-151080BF7796@khptech.com> <CA%2BWntOsjc6X329ujtxwgJP1=JceVu__=khntX9F2cVokKZq6eg@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Not sure where the the intermediate emails on this thread went, so I'll jump in again. On 02/21/12 03:50, Super Bisquit wrote: > . > On 2/19/12, Kevin H. Patterson<kpatterson.home@gmail.com> wrote: >> I am interested in raw cpu integer and floating-point performance only, at >> this point. This is *exactly* what simple synthetic benchmarks (like ubench) >> are for. There is absolutely NO reason why performance should be 3x better >> running under macosx than under freebsd, on the exact same hardware. > > Things happen that way. I've ran a firefox benchmark on different > architecture running different systems and received different results. On G5s that I know are properly configured (a dual-core Powermac and an iMac), numerical code runs at exactly equal speed on the two operating systems, or a little faster on FreeBSD if it spends a lot of time in the math library (Apple appears to have optimized system binaries with -Os in 10.5 for PowerPC, which pessimizes performance). If you have purely numerical code (check md5 -t, which both OSes have) with large offsets then something is clearly not set up correctly. Did you have a chance to check the reported CPU speed in dmesg? Also, did you boot from the OF prompt or via autoboot? Some Apple G5 systems will slow the CPU and bus by large factors, in a way FreeBSD can't yet correct, if you start from an OF prompt. -Nathan
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4F429E9B.4040500>