Date: Fri, 4 Oct 2002 10:14:43 -0500 From: "Schroeder, Aaron" <Aaron.Schroeder@qg.com> To: "'chris@evilelement.net'" <chris@evilelement.net>, freebsd-alpha@FreeBSD.org Subject: RE: Alpha PWS 500au SCSI Transfer Rate Message-ID: <025596A38A894B45AFE62346A6BF47464E2E97@waexch1.qgraph.com>
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IICRC, those Qlogic 1020/1040 cards were only fast-wide cards and not Ultra... Your new hard drive may be Ultra SCSI, but in order to talk to the card, the drive has downgraded itself to fast wide. If you get an ultra wide card, you will see the 40Mb figure. In reality, you'll never see those transfer rates anyways. The 20MB and 40MB numbers are just that: numbers. In reality, the most you will get off any given Ultra-Wide/Fast-Wide SCSI chain is anywhere from 7-12Mb a sec, and that's flying. Ultra160 and Ultra320 are completely different scenarios, those busses absolutley scream! AJ Schroeder -----Original Message----- From: Chris Brotherton [mailto:chris@evilelement.net] Sent: Thursday, October 03, 2002 11:09 PM To: freebsd-alpha@FreeBSD.org Subject: Alpha PWS 500au SCSI Transfer Rate I am a newbie to both SCSI and FreeBSD. I have a Digital PWS 500au with an on board Qlogic 1040B Ultra Wide SCSI Controller. I used to have an IBM Fast wide SCSI hard drive that was correctly probed with the following message in dmesg. da0 at isp0 bus 0 target 0 lun 0 da0: <IBM DCHS04W 2722> Fixed Direct Access SCSI-2 device da0: 20.000MB/s transfers (10.000MHz, offset 8, 16 bit), Tagged Queueing Enabled I recently replaced this hard drive with a new Seagate ST336706LW - 36ES. I notice the following dmesg. da0 at isp0 bus 0 target 0 lun 0 da0: <SEAGATE ST318406LW 010A> Fixed Direct Access SCSI-3 device da0: 20.000MB/s transfers (10.000MHz, offset 8, 16 bit), Tagged Queueing Enabled My question is: Why doesn't this drive operate at 40.000MB/s since it is backwards compatible with Ultra Wide SCSI? Do I need to set something up in the SRM before booting FreeBSD? Here is the SCSI controller detection lines from dmesg: isp0: <Qlogic ISP 1020/1040 PCI SCSI Adapter> port 0x8000-0x80ff mem 0x81080000-0x81080fff irq 3 at device 4.0 on pci1 isp0: interrupting at CIA irq 3 Thanks for your help. Chris. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message
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