G.FUSSELL@SCORE.STANFORD.EDU (Carl Fussell) (05/09/88)
My appologies if you have seen this but since I sent this out a few days ago and haven't seen it come back over Info-VAX, I thought I'd try it again... --------------------------- I was hoping that the experience of readers of this list might be able to help us... Our site needs to add some additional disk storage to our system. Presently, all our existing drives are vanilla DEC (predominently RA81 drives hanging off an HSC50). We are thinking about trying non-Dec drives for the first time. We'll be making a choice in about a week and a half and DEC is slipping daily... Does anyone have any experience, comments, or advice on alternative vendors we might look at for drives in the 1/2GB - 1GB capacity range? In particular, we are looking at SI and Emulex but comments on others would be welcome and appreciated. Are non-Dec solutions reliable? How's the performance? Are there maintenance problems (all our current hardware is under Dec service agreements)? When problems do arise, does a lot of "finger pointing" occur? An so on... Thanx in advance for any help. (if there is an interest, I would be happy to either post results or summarize it) Carl Fussell Santa Clara Univ G.FUSSELL@SCORE.STANFORD.EDU CARL@SCU.BITNET -------
kenw%noah.arc.CDN@ean.ubc.ca (Ken Wallewein) (05/16/88)
We use a CDC XMD-II on our system, with a Sigma controller. Digital Review uses the same drive with a Dilog controller. An Emulex controller is also available. The drive is very nice: 850 Mb unformatted about 700 formatted 16 ms. _average_ seek time 1 Mb on-board cache on the controller I've seen our I/O rate hit 120 on this drive on a uVAXII. Try THAT on any DEC drive you can find. And right now I can get one for $9000 CDN. Works good, lasts long time. On the other hand, we've had some interesting problems with what appears to be signal reflection on the backplace, recently. Looks like the Sigma controller, best guess, but Sigma's been kinda slow in helping to find out for sure. I posted a message about it during the latest Great News Blackout - did anybody see it? /kenw
pstevens@pioneer.arpa (Paul Stevens RCE Sterling) (05/19/88)
In article <1501*kenw@noah.arc.cdn> you write: > > We use a CDC XMD-II on our system, with a Sigma controller. Digital Review >uses the same drive with a Dilog controller. An Emulex controller is also >available. > I also support a uVAX system here with the same drives but with the Dilog controller. We had no problems with the controller and bus terminations, but we did have problems with our Sigma expansion cabinet. It seems they forgot to mention that you have to remove some resistors in the BA23 when adding their cabinet as an expansion box. I also have good experience with the XMD, we bought it to use in a high speed data acquistion environment and our intial tests show we'll be able to perform sustained rates of >1 Mbyte/sec to disk using optimized writing techniques. I don't think of this so much as a plug for CDC but as a plug for using the SMD-E interface. Or at least anything *BUT* ST506/RDxx toys. ----------------------------------------------------------------------- Paul Stevens - NASA Ames Research Center Moffet Field CA Mail Stop 233-10 (415)694-4887 pstevens@ames-pioneer.arpa