[Beowulf] More about those underwater data centers

[Chris Samuel]

On Monday, 5 November 2018 3:13:29 AM AEDT John Hearns via Beowulf wrote:

> Have we faced up to the environmental impact of this? 

Where I've been has always tried to reuse/resell/recycle systems.  Our 
alphacluster was snapped up by folks in the US, our first Intel cluster went 
to another university, our Power5 cluster went somewhere I can't remember. At 
${JOB-1} we had Intel clusters redirected to other parts of the university 
(including one to the LHC ATLAS folks there). BlueGene - well not so much as 
far as I could tell. :-(

> It is often said that CPUs can be upgraded - I have only once seen an
> upgrade in place in my career.

Only been offered (and did) this once about a decade ago at ${JOB-2} where we 
upgraded a system from dual core to quad core Opteron (Barcelona).

That could have gone.... better...  First of all it was all delayed because of 
the TLB errata (we eventually got affected chips and ran with the kernel patch 
before getting the rev'd silicon) and then we started to see random lock ups.

Turned out (after a lot of chasing) that whilst the mainboard was meant to be 
OK the layout in the box meant the RAM next to the CPUs would sometimes 
overheat and take down the box.   They added some heatsinks to those DIMMs and 
the problem went away!

All the best,
Chris
-- 
 Chris Samuel  :  http://www.csamuel.org/  :  Melbourne, VIC