[Beowulf] Earthquakes and raised floors...

[Jim Lux]

At 11:53 AM 1/6/2006, Robert G. Brown wrote:
>J
>
>Earthquakes are only ONE reason (although a very good one).  As the
>article points out and backs up with numbers, NO data center with a
>raised floor can honestly claim 5 nines in reliability, since if a
>single major earthquake occurs every 100K years the average damage done
>to supposedly earthquake-proof data centers in major seismic events of
>the last decade drops the mean expected uptime below five nines.
>
>However, it runs down a whole list of reasons for the use of raised
>floors in the first place, one at a time, and indicates that
>requirements for data centers have evolved to obsolete them.  For
>example, at one time the floor was a room-spanning ground (needed to
>prevent ground loops on the network).  Now modern cables prevent ground
>loop problems out to a radius of 50-100m, and electrical wiring up to
>code to a room panel are adequate to mostly prevent problems on close to
>the same scale.


<snip>

You forgot the cooling fluid lines for your mainframe.  The bigger S/360 
machines were liquid cooled.  A raised floor is VERY nice when that cooling 
line leaks.


James Lux, P.E.
Spacecraft Radio Frequency Subsystems Group
Flight Communications Systems Section
Jet Propulsion Laboratory, Mail Stop 161-213
4800 Oak Grove Drive
Pasadena CA 91109
tel: (818)354-2075
fax: (818)393-6875