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Bob, Here's an answer about replacing an IRIX box with a pc but the ideas about the LDM architecture are correct for any box, ie Octane. Robb... From address@hidden Tue Mar 2 14:57:15 1999 Date: Tue, 2 Mar 1999 12:34:10 -0700 From: Mike Schmidt <address@hidden> To: Peter Neilley <address@hidden>, address@hidden Subject: Re: Replacement IITA machine Peter, Here's my .02. I recall that IITA suffered as much from a sluggish I/O system as it did from lack of memory. I'd prioritize as follows (based on experience with IITA and our LDM systems); - fastest I/O subsystem possible (ultra2/wide/lvd/10Krpm scsi disks) with enough disk capacity to meet your needs - depending on your decoding needs, you might consider low end RAID - as much memory as possible - 768 MB (or enough for LDM queue) - dual 400+ MHz processors (any Pentium II should work fine) Buying the latest Intel processors (Pentium III/Xeon) is too expensive to justify within the budget constraints you mention - fast network interface (100baseT is cheap anyway) It's easy and relatively cheap to add PC commodity disk and memory later if you underestimate -- presuming all the slots/drive bays are not filled. Changing the I/O bus (and the disks) or the CPU's are much more costly. For reference, our current LDM system is a Sun Ultra 2 with 2x300MHz CPU's, 1GB memory, ultra wide scsi with ~11 ms access disks (no RAID) and 100baseT. Both the disks and the memory are always hammered. The CPU's run along about 50-70% idle, and the network load is very low. mike > > ------- Forwarded Message > > >To: address@hidden > >cc: address@hidden > >From: "Bob Creasey" <address@hidden> > >Subject: ldm ? > >Organization: . > >Keywords: 199903022129.OAA24383 > > Hello, > > I am considering a dual processor SGI Octane (IRIX6.5 512mb mem) to run our > LDM > and product generation. I was wondering if you had an opinion on whether a > dual processor system would work well with the ldm environment and products or > if the IO required made a single processor just as effective? Normally, I > would just keep with a single processor and fan out to other machines when > loading became an issue at peak times. Our current system is a single > processor ELAN and it never sees a dull moment...I have to shoe horn in any > new > tasks during processing gaps to keep it from blowing up. > > Anyway I would be interested in your comments? > > Thanks, > Bob > > -- > Bob Creasey ( +*)) (+ * )_ > Naval Postgraduate School ((* - * )(++,, , )) > Dept of Meteorology Rm 254 MR/CY (( ,- *- ,, -,- ), ))__ > 589 Dyer Rd. (_______________________)) > Monterey Ca 93943-5114 \ \ \\\\\\\ > address@hidden / \ /\_ \\\\\\ > Work Phone: 1-831-656-3178 / / / \ \\\\\ > DSN: 878-3178 FAX: 1-831-656-3061 > > > ------- End of Forwarded Message > =============================================================================== Robb Kambic Unidata Program Center Software Engineer III Univ. Corp for Atmospheric Research address@hidden WWW: http://www.unidata.ucar.edu/ ===============================================================================