Hi Kem, Per the definitions in the SRD, we should be estimating to the design spec. We consider the stretch goal if it does not materially increase cost, schedule, or risk. In this case, the stretch goal would appear to significantly increase cost.
Jeff > From: "Kem Cook" <[EMAIL PROTECTED]> > Reply-To: LSST Data Management <[email protected]> > Date: Wed, 12 Jul 2006 13:25:45 -0700 (PDT) > To: "LSST Data Management" <[email protected]> > Subject: Re: [LSST-data] Notes from Database telecon Wed Jul 12 > > Keywords: DataAccWG >> database storage estimates >> - latest version uses input from Zeljko, database size >> increased by ~50% >> - now it is 600 TB data after the first year >> - Tim: number of sources seems too large, will check the >> spreadsheet in more details and start email discussion > > The current numbers use the number of visits per field-filter needed for > the weak lensing for all fields and this is clearly not correct for the > Galactic plane/bulge fields. It is those fields in the red filters which > are driving the number of objects. So, the catalog has the correct > numbers, but the temporal database is overestimated. I thought the > science council was going to provide some guidance on observing > cadences/frequencies for Galactic fields, but haven't heard anything. > Until we have an idea what the cadences/frequencies are we might as well > stick with the conservative (overly large) estimate we have. > > I must admit to a bit of sloppiness in mixing design and stretch goals. > We have been assuming 1000 visits for the weak lensing fields (design > goal) and 20,000 square degrees (stretch goal). So, a question for Jeff > (&Tim) should we be sizing for the design numbers or the stretch numbers? > _______________________________________________ > LSST-data mailing list > [email protected] > http://www.lsstmail.org/mailman/listinfo/lsst-data > _______________________________________________ LSST-data mailing list [email protected] http://www.lsstmail.org/mailman/listinfo/lsst-data
