Hi Pierre,
I confirmed with the guy who put together the machine that it is non-ECC
RAM. You know, now that i think about it, this machine seems to crash a
fair amount more often than its identical twin which sits on a desk near me.
I researched memtest a bit... downloaded and compiled it, but I do not quite
understand the finer points of using it... it seems that I want to remove my
RAM cards and test them one at a time. Do you know a good reference for
using it.
I think at this point the best thing to do will be to dump my data/code to
portable HDD and load it on the other computer with same specs as this one.
If it runs without generating any NaN then I will proceed to a full memtest.
Thanks for the advice.
-Karl
Joe Kington-2 wrote:
>
> On Thu, Dec 1, 2011 at 2:47 PM, kneil <magnetotellur...@gmail.com> wrote:
>
>>
>> Hi Pierre,
>> I was thinking about uploading some examples but strangely, when I store
>> the
>> array using for example: np.save('Y',Y)
>> and then reload it in a new workspace, I find that the problem does not
>> reproduce. It would seem somehow to be
>> associated with the 'overhead' of the workspace I am in...
>>
>
>> The context here is that I read in 24 files, totaling about 7GB, and then
>> forming data matrices of size 24 x N, where N varies. I tried for
>> example
>> this morning to run the same code, but working with only 12 of the files
>> -
>> just to see if NaNs appeared. No NaN appeared however when the machine
>> was
>> being less 'taxed'.
>>
>
> Are you using non-ECC RAM, by chance? (Though if you have >4GB of ram, I
> can't imagine that you wouldn't be using ECC...)
>
> Alternately, have you run memtest lately? That sound suspiciously like
> bad
> ram...
>
>
>>
>> Strangely enough, I also seterr(all='raise') in the workspace before
>> executing this (in the case where I read all 24 files and do net NaN) and
>> I
>> do not get any messages about the NaN while the calculation is taking
>> place.
>>
>> If you want to play with this I would be willing to put the data on a
>> file
>> sharing site (its around 7.1G of data) together with the code and you
>> could
>> play with it from there. The code is not too many lines - under 100
>> lines,
>> and I am sure I could trim it down from there.
>>
>> Let me know if you are interested.
>> cheers,
>> K
>>
>>
>> Pierre Haessig-2 wrote:
>> >
>> > Le 01/12/2011 02:44, Karl Kappler a écrit :
>> >> Also note that I have had a similar problem with much smaller arrays,
>> >> say 24 x 3076
>> > Hi Karl,
>> > Could you post a self-contained code with such a "small" array (or even
>> > smaller. the smaller, the better...) so that we can run it and play
>> with
>> > it ?
>> > --
>> > Pierre
>
>
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