Hi Mark,
This may be a little late, but here are the latest spreadsheet (and
it's explanation) used to compute the predicted GlueX disk space. The
main thing you'll notice is that there is virtually no disk space
allocated for simulation. This was mainly due to a calculation that it
costs more to store the simulated data than reproduce it. As such, we
wanted the IT division to focus their budget on more CPU power for the
farm as opposed to work disk space. This is not to say that philosophy
should still be followed, just that that was the motivation in the past.
You are likely to get questions from Sandy and Chip referring back to
the spreadsheet.
Regards,
-David
Mark M. Ito wrote:
> In recent months we have run out of space on our works disk from time
> to time. Our activity generating and reconstructing simulated data is
> ramping up. We discussed the situation in the Hall D Offline Meeting
> and we would like request more space. Our current allocation is 2.7
> TB. We request that this be increased to 5 TB as soon as possible and
> that the total be increased to about 10 TB over the next year.
>
> Once in operation, the GlueX detector will generate a large volume of
> data. To be ready to analyze real data once it comes in we will have
> to generate large amounts of simulated data to develop and test all
> the of necessary tools well in advance of the arrival of real data. As
> we approach operations we will likely need an amount of space equal to
> or exceeding the amount used by Hall B (about 35 TB). Recall that raw
> data is generally not stored on the work disks in any case, work space
> is used for intermediate files needed to analyze raw or simulated
> data. The fact that GlueX has not taken real data yet does not imply
> our current disk needs are insignificant. We note that this request is
> quite modest when compared to the total amount of work disk space
> deployed at present.
>
>
--
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David Lawrence Ph.D.
Staff Scientist Office: (757)269-5567 [[[ [ [ [
Jefferson Lab Pager: (757)584-5567 [ [ [ [ [ [
http://www.jlab.org/~davidl davidl@jlab.org [[[ [[ [[ [[[
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12 GeV Computing Worksheetsv2.xls