Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!caen!spool.mu.edu!cs.umn.edu!uc!shamash!timbuk!sdm From: sdm@sequoia.cray.com (Stuart Mitchell) Newsgroups: comp.sys.amiga.hardware Subject: SUMMARY (longish) Re: Whats a good choice of SCSI HD ? Message-ID: <085021.10141@timbuk.cray.com> Date: 7 Jun 91 17:17:52 GMT Article-I.D.: timbuk.085021.10141 Sender: sdm@sequoia (Stuart Mitchell) Organization: Cray Research, Inc. Lines: 70 Well, it's now about 3 weeks since I posted my original question asking "whats a good choice of SCSI HD to hang off an A590", and quite a lot has happened in that time - I thought I'd post a summary of my experiences as there seemed to be some interest (from mail I received). Anyway, after my initial article I received several mail replies, the majority of which recommending Quantum as a good choice of drive. In fact one of the mails was actually an offer to sell a 105MByte Quantum for $300, from somebody in California, which I thought was quite a good deal. So I went ahead and negotiated to buy this drive - the only problem being that I live in the UK, so there were a few logistic problems concerned with getting a drive from California to the UK. It arrived the beginning of last week, but I didn't get around to doing anything with it til last weekend, as I was away for the week. I knew from reading the 590 manual that there was an internal SCSI connector as well as the external interface, so I thought the easiest way was to replace the existing Western Digital XT drive with the Quantum (using the existing A590 casing etc). After making up a SCSI ribbon cable I transferred the Quantum into the 590 controller and tried powering it up (booting from the 590 setup floppy) and it worked !! These things must be a lot more resilient than people make out - after travelling more than 6000 miles via UPS and courier I was concerned whether it would spin up at all, and so was somewhat relieved when it did. So, having preped it I had to swap back the WD 20Meg drive to retrieve the data from it (I know, I should have had full backups already, but it was a good reason to do some cleaning up anyway :-). After backing up approx 15Mbytes onto floppies I put the Quantum back in the controller, setup my favourite partitioning scheme, and restored all the stuff from floppies. [Aside: any opinions out there about what's a "good" partitioning scheme for HD's ?] I wasn't sure if there was a "net accepted" method used for measuring hard disk performance, so I grabbed a copy of "DiskSpeed" off fish disk 329 and used that as it seemed to be a reasonable choice. And here are the results (all using 250kbyte buffers) - Max. transfer rates (measured using DiskSpeed 2.0) -------------------------------------------------- WD 20M: read: 154 kbytes/s ( 20% of RAM:) write: 123 kbytes/s ( 16% of RAM:) Q 100M: read: 624 kbytes/s ( 83% of RAM:) write: 583 kbytes/s ( 77% of RAM:) RAM: read: 750 kbytes/s (100% of RAM:) write: 750 kbytes/s (100% of RAM:) A marked improvement over the old XT drive !! I have to admit that this whole exercise turned out to be a lot easier than I expected, so I would recommend this technique for upgrading your harddisk capacity. And finally, a couple of questions: When I try and issue a "park" command it returns the error "Can't find Rigid Disk Block!" - does this indicate some kind of problem with the drive ? Or does the drive autopark anyway ? (in which case I guess explicit parking isn't that important) Suggestions for what can I do with the old 20Meg disk ?? - I guess I could put it back in the 590, put the Quantum in a separate case and use the external SCSI connector for the Quantum.....or is it possible to have both the internal connectors in the A590 in use at the same time ? Stuart (sdm@uk.cray.com)