Re: e-clerk computer

[Seth Teller <teller@lcs.mit.edu>]

jon and i discussed RAID, and decided we didn't need high
performance I/O or high reliability at this point.  we plan
to go with a regular disk.  one possibility would be to
mirror or cross-mount it to the graphics domain, which is
regularly backed up to DAT.

seth

David R. Karger wrote:
> Only issue I wonder about: should we bother with raid, backup, etc on
> our machine or should we "outsource", using a drive on the network
> somewhere that already gets backed up by sysadmins?
> 
>    Date: Tue, 13 May 2003 16:22:30 -0400 (EDT)
>    From: Jonathan Wolfe <jwolfe@graphics.lcs.mit.edu>
>    cc: sfc@graphics.lcs.mit.edu
>    X-SBPass: Local Origin
> 
>    Just met with Adel, here's suggested machine stats and our conclusions:
> 
>    Dual 2.8GHz Dell Workstation
>    2GB RAM
>    No Monitor
>    ATI Radeon 32MB VGA video card
>    146GB Ultra 320 SCSI Harddrive
>    No installed OS (Adel says we can install what we want)
>    48X cd-rom
>    Integrated U320 SCSI controller
> 
>    approximate price - somewhere in between $4k and $5k (Dell won't give me a 
>    web site price without an OS, I'll have to call them later).
> 
>    For a set amount of money to spend, it would most likely be more 
>    beneficial to get a 2-proc machine with faster processors than a 4-proc 
>    machine with slower processors.  However, it is, of course, always better 
>    to have more computation power.
> 
>    Therefore (based on prices of Dell machines below), it makes sense to buy 
>    a powerful 2-proc machine - the least powerful 4-proc machine is over 2.5 
>    times more expensive than the 2-proc machine.
> 
>    Dual Xeon 3.0GHz (512K cache) - ~$6k
>    Quad Xeon 1.5GHz (1MB cache)  - ~$15.7k
>    Quad Xeon 1.9GHz (1MB cache)  - ~$19.9k
>    Quad Xeon 2.0GHz (2MB cache)  - ~$28.8k
> 
>    One question:
> 
>    I don't see any need for gigabit ethernet on this machine, it seems that 
>    the built-in 100MB ethernet would be sufficient.  Is there any part of the 
>    design that I might be missing here?
> 
>    A few random notes as well:
> 
>    With Linux, you can't bind processes to CPUs, you just have to put up with 
>    what the Unix scheduler assigns.  Linux kernels certainly support multiple 
>    processors just fine, you just can't bind to a single processor.
> 
>    More than 2GB RAM probably isn't worth it, but if we ever need more 
>    memory, it's not that expensive to get more.
> 
>    We should use the USB interface for the scanner and not the SCSI as it 
>    will simplify having SCSI hard disks.  We can always put another 
>    controller in the box to use the SCSI scanner interface if USB turns out 
>    to be a bottleneck.
> 
>    Regarding RAID, even without hardware RAID we could choose to use software 
>    RAID and 2 hard disks, although that would slow down writes a little.  
>    Alternatively, without RAID we could just depend on disk backups.
> 
>    -Jon
> 
>