Date: Thu, 20 Jan 2005 20:27:39 +0100 From: martin hudec <corwin@aeternal.net> To: freebsd-stable@freebsd.org Subject: Re: Higher ATA-Mode -> lower speed Message-ID: <20050120192739.GD5431@pleiades.aeternal.net> In-Reply-To: <200501202000.43688.emanuel.strobl@gmx.net> References: <200501201948.42707.emanuel.strobl@gmx.net> <200501202000.43688.emanuel.strobl@gmx.net>
next in thread | previous in thread | raw e-mail | index | archive | help
[-- Attachment #1 --] Hello, On Thu, Jan 20, 2005 at 08:00:39PM +0100 or thereabouts, Emanuel Strobl wrote: > > > > I observed a strange behaviour which seems to explain my often noticed > > "16MB/s hard-limit" > > > > I have a UDMA133 drive (MAXTOR 6L060J3) which saturates at 16MB/s when I > > dump anything to it, regardless of the block size. This transfer rate is > > reached with bs=4k and doesn't increase any more even not with bs=64k. > > > > Can anybody confirm that for different hw? Especially people like fandino > > who already discussed poor ata performance on -current (~16 Oct. 04). my tests shows speeds ranging from 36.9MB/s up to 59.3MB/s. System is 6.0-CURRENT (yup I know this is -stable list), built on Jan 10, 2005 with VIA 8235 UDMA133 controller. Disk configuration is as following: ad0: 38172MB <MAXTOR 6L040J2/AR1.0400> [77557/16/63] at ata0-master UDMA133 ad1: 39205MB <Maxtor 2F040J0/VAM51JJ0> [79656/16/63] at ata0-slave UDMA133 /usr is located on /dev/ad0s1e, and /various is located on /dev/ad1s1d. Testing of ad0: pleiades# dd if=/dev/zero of=/usr/testfile bs=4k count=2000 8192000 bytes transferred in 0.161283 secs (50792701 bytes/sec) pleiades# dd if=/dev/zero of=/usr/testfile bs=16k count=2000 32768000 bytes transferred in 0.792992 secs (41321975 bytes/sec) pleiades# dd if=/dev/zero of=/usr/testfile bs=64k count=2000 131072000 bytes transferred in 3.386982 secs (38698759 bytes/sec) Testing for ad1: pleiades# dd if=/dev/zero of=/various/testfile bs=4k count=2000 8192000 bytes transferred in 0.131618 secs (62240716 bytes/sec) pleiades# dd if=/dev/zero of=/various/testfile bs=16k count=2000 32768000 bytes transferred in 0.674646 secs (48570665 bytes/sec) pleiades# dd if=/dev/zero of=/various/testfile bs=64k count=2000 131072000 bytes transferred in 3.184140 secs (41164020 bytes/sec) I also run these tests on another machine shows speeds ranging from 49MB/s up to 63MB/s. System is 5.3-STABLE built on Dec 7, 2004 with SiS 735 UDMA100 controller. Disk configuration is as following: ad0: 76319MB <WDC WD800JB-00ETA0/77.07W77> [155061/16/63] at ata0-master UDMA100 /usr is located on /dev/ad0s1e. Testing of ad0: amber# dd if=/dev/zero of=/usr/testfile bs=4k count=2000 8192000 bytes transferred in 0.154835 secs (52907939 bytes/sec) amber# dd if=/dev/zero of=/usr/testfile bs=16k count=2000 32768000 bytes transferred in 0.495422 secs (66141576 bytes/sec) amber# dd if=/dev/zero of=/usr/testfile bs=64k count=2000 131072000 bytes transferred in 2.546718 secs (51467023 bytes/sec) I hope that this information will help you. Cheers, Martin -- martin hudec * 421 907 303 393 * corwin@aeternal.net * http://www.aeternal.net "Nothing travels faster than the speed of light with the possible exception of bad news, which obeys its own special laws." Douglas Adams, "The Hitchhiker's Guide to the Galaxy" [-- Attachment #2 --] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (FreeBSD) iD8DBQFB8AYrZYEZIv+rgggRAlyQAJ93v/Np7hiT91V7alHQ+nfPJTy0pgCgly9R sdTVkNzAvriJjVNAMGYrrW8= =xVnu -----END PGP SIGNATURE-----
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050120192739.GD5431>