Date: Sun, 23 Aug 1998 21:48:01 -0500 From: Dan Nelson <dnelson@emsphone.com> To: David Kott <dakott@alpha.delta.edu>, hackers@FreeBSD.ORG Subject: Re: Adaptec 1542i Performance on -stable [was Re: SCSI Controller] Message-ID: <19980823214801.A24497@emsphone.com> In-Reply-To: <Pine.BSF.3.96.980821183753.26738A-100000@kott.my.domain>; from "David Kott" on Fri Aug 21 18:58:57 GMT 1998 References: <xzpg1er369x.fsf@hrotti.ifi.uio.no> <Pine.BSF.3.96.980821183753.26738A-100000@kott.my.domain>
next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Aug 21), David Kott said: > I am using a 1542 right now on this -stable machine. While I am not > particularily overwhelmed by it's performance, I have had no problems > that I could definately link to the adapter itself. Perhaps I have not > configured it for optimal performance. > > root@kott [/root]# dd if=/dev/rsd0a of=/dev/null count=1024 > 1024+0 records in > 1024+0 records out > 524288 bytes transferred in 3.619458 secs (144853 bytes/sec) > > root@kott [/root]# dd if=/dev/rwd2s1a of=/dev/null count=1024 > 1024+0 records in > 1024+0 records out > 524288 bytes transferred in 0.173658 secs (3019083 bytes/sec) Try rerunning both dd lines with a bs=64k argument; the SCSI bus has a larger per-operation overhead then the IDE bus, and forcing it down to 512-byte transfer chunks isn't really a good benchmark. The 1542 support is quite good as far as I can tell; we use an old Compaq 486/66 and a 1542 as a tape drive machine, and I used to have a 1542 as my main SCSI controller until I got a 2940. -Dan Nelson dnelson@emsphone.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19980823214801.A24497>