Date: Fri, 14 Jan 2000 14:25:17 -0800 (PST) From: Rick Hamell <hamellr@aracnet.com> To: Micke Josefsson <mj@isy.liu.se> Cc: freebsd-questions@FreeBSD.ORG Subject: Re: Expected SCSI speed question Message-ID: <Pine.LNX.4.10.10001141421540.11522-100000@shell1.aracnet.com> In-Reply-To: <XFMail.000114094500.mj@isy.liu.se>
next in thread | previous in thread | raw e-mail | index | archive | help
> I have a 200 MHz K6 system (FBSD 3.2), Adaptec 2940UW SCSI-adaptor and Seagate > ST19171W Hard disk. The Seagate (Barracuda 9) disk is specced to up to 40 > Mbytes/sec Max sync. SCSI transfer rate. But whatever tests I run (copying > large files to and fro, dd from disk to /dev/null for example) the actual speed > is never more than around 0.5 MB/s according to 'systat -io 1' or 'systat -vm > 1'. > > Is there a knob to turn to speed it up or is this a bottleneck due to the > processor? I've noticed that the Adaptec 2940UW seems to be a fairly slow card, at this point I'm pulling every single one I come across and replacing with Tekram cards. The biggest differance I saw was doing a drive mirror under Novell 3.12 a couple of weeks ago. Dual 2940s with their own seperate drives took 3 hours. Using the exact same model drive and two of the Tekram cards took under 20 minutes. Under FreeBSD I've seen similar performance. :( Rick To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.LNX.4.10.10001141421540.11522-100000>