I guess I am not clear on what would be contained in the older releases. In some (most?) projects, the newer releases supercede (and include) the contents of the older releases. I suppose the older releases do include unique calibrated data products that were calibrated under some prior version of the data processing/calibration algoriths. In that case, I can see some utility and value in having the older releases available. However, having these releases instantly accessible on spinning disks (versus archival backup media) is another issue.
- Kirk > Date: Tue, 11 Jul 2006 15:56:10 -0700 > From: Jacek Becla <[EMAIL PROTECTED]> > Subject: [LSST-data] disk space for old releases > To: LSST Data Management <[email protected]> > > Keywords: DataAccWG > > Hello, > > In our current disk storage estimates we are assuming we will need > disk space for 2 most recent releases and unreleased catalog. > But what about the disk space for older releases that some people might > want to stage in from tape? That is not included in the estimates. > How much should we reserve for that? Equivalent of size of the most > recent release? > > BTW, if we end up being limited by disk IO and not space, we will > get that "space for free" anyway, BUT... it is important to get > an idea how much disk space we will need because disk io pushes us > towards smaller disks (which are faster, have better seek time), > so we can end up in a situation where required number of > small disks does not give us enough disk space (I went through > the numbers with Don and that can happen). I'm in the process > of building a model for that. > > > Jacek _______________________________________________ LSST-data mailing list [email protected] http://www.lsstmail.org/mailman/listinfo/lsst-data
