Date: Fri, 8 Aug 1997 02:20:54 -0500 (EST) From: "John S. Dyson" <toor@dyson.iquest.net> To: bag@sinbin.demos.su (Alex G. Bulushev) Cc: toor@dyson.iquest.net, freebsd@atipa.com, dyson@FreeBSD.ORG, ggm@connect.com.au, current@FreeBSD.ORG Subject: Re: IDE vs SCSI was: flags 80ff works (like anybody doubted it) Message-ID: <199708080720.CAA00770@dyson.iquest.net> In-Reply-To: <199708080713.LAA26524@sinbin.demos.su> from "Alex G. Bulushev" at "Aug 8, 97 11:13:09 am"
next in thread | previous in thread | raw e-mail | index | archive | help
> > This is the result of my "slow" recent, but not the latest, greatest > > IDE drive (WD 4GB drive.): > > > > Command overhead is 88 usec (time_4096 = 348, time_8192 = 607) > > transfer speed is 1.57828e+07 bytes/sec > > > > dd if=/dev/rwd1 of=/dev/null count=1600 bs=64k > > 1600+0 records in > > 1600+0 records out > > 104857600 bytes transferred in 10.881267 secs (9636525 bytes/sec) > > > > This is results for Seagate Barracuda 9GB on second channel of > adaptec 3940UW (no TAG, MEMIO etc in kernel): > > dmesg output: > ------------- > Probing for devices on PCI bus 2: > ahc2 <Adaptec 3940 Ultra SCSI host adapter> rev 0 int a irq 11 on pci2:4 > ahc2: aic7880 Wide Channel A, SCSI Id=7, 16 SCBs > ahc2 waiting for scsi devices to settle > (ahc2:0:0): "SEAGATE ST19171W 0023" type 0 fixed SCSI 2 > ^^^^^^^^^^^^^^^^^^^^^ > > > dd output: > ---------- > dd if=/dev/rsd7e of=/dev/null count=1600 bs=64k > 1600+0 records in > 1600+0 records out > 104857600 bytes transferred in 9.480124 secs (11060784 bytes/sec) > ^^^^^^^^^^^^^^^^^^ > What is the command overhead? John
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199708080720.CAA00770>