Date: Wed, 2 Sep 2009 16:36:29 +0200 From: Olivier Smedts <olivier@gid0.org> To: Emil Mikulic <emikulic@gmail.com> Cc: "Derek \(freebsd lists\)" <482254ac@razorfever.net>, freebsd-current@freebsd.org Subject: Re: siis/atacam/ata/gmirror 8.0-BETA3 disk performance Message-ID: <367b2c980909020736i60b64563xc4fec6d11e3dae2b@mail.gmail.com> In-Reply-To: <20090902141138.GA15045@dmr.ath.cx> References: <4A9E5F34.2090700@razorfever.net> <20090902141138.GA15045@dmr.ath.cx>
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2009/9/2 Emil Mikulic <emikulic@gmail.com>: > On Wed, Sep 02, 2009 at 08:04:04AM -0400, Derek (freebsd lists) wrote: >> Hi, >> >> I've been testing the new siis driver, and I have found no >> appreciable performance change, using dd as a measure of "raw" >> performance. >> >> I get about 40MB/s read, and 30MB/s write. =A0See attached >> bench-*.txt files. > > [...] > >> ada0: <ST31500341AS CC1H> ATA/ATAPI-8 SATA 2.x device >> ada0: 1430799MB (2930277168 512 byte sectors: 16H 63S/T 16383C) > > Huh, I have the same disk: > > # dmesg | grep ad4 > ad4: 1430799MB <Seagate ST31500341AS CC1H> at ata2-master SATA300 > > Sequential read on a disk this size should be around 120MB/sec at the > outer tracks: > > # dd if=3D/dev/ad4 of=3D/dev/null bs=3D128k count=3D5000 > 655360000 bytes transferred in 5.171389 secs (126728039 bytes/sec) > >> Also I find it surprising that my gmirror read is only 40MB/s, >> and not 60-80MB/s, any thoughts on this? > > Stripe will give you higher throughput. > Mirror will give you more random seeks per second. And higher read throughput. > > --Emil > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org= " > --=20 Olivier Smedts _ ASCII ribbon campaign ( ) e-mail: olivier@gid0.org - against HTML email & vCards X www: http://www.gid0.org - against proprietary attachments / \ "Il y a seulement 10 sortes de gens dans le monde : ceux qui comprennent le binaire, et ceux qui ne le comprennent pas."
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