[Beowulf] Re: ECC Memory and Job Failures

[David Mathog]

> From: Vincent Diepeveen <diep at xs4all.nl>
> Subject: Re: [Beowulf] Re: ECC Memory and Job Failures (Huw Lynes)


> However i noticed that if i saved my tapes (Ultrium2-200GB  
> uncompressed, 400GB according to the salesman) at
> about 1 meter above the ground here, things go fine. Yet if i save  
> them at 2nd floor here that is more risky.
> There is definitely more bitflips there. Now that is a lot closer to  
> the 2 x 450 MVA powerlines, which are on average at a height of about  
> 19 meters above ground,
> a bit less when a lot of power is on 'em, as the cables tend to get  
> very hot then.

Before blaming the power lines I would first rule out a large local
magnetic field from some other source.  There isn't by any chance an NMR
machine, cyclotron, power transformer, large electric motor, etc. in
that vicinity?

Regards,

David Mathog
mathog at caltech.edu
Manager, Sequence Analysis Facility, Biology Division, Caltech