[lsst-dm-stack-users] stack build can be *very* memory hungry -- default to fewer NCORES?

[Dustin Lang]

Hi,

On my Mac OSX 10.8 laptop with 4 cores and 8 GB of memory, the machine 
becomes nearly unusable during the afw build.  I would think this would be 
a fairly standard target machine for our users, so I would suggest that we 
might want to highlight (and fix the errors in) the description of how to 
make the build use fewer cores.  Or perhaps just crank down the default to 
not fully max out the number of cores.

The instructions at the bottom of this page appear to be out of date:
https://confluence.lsstcorp.org/display/LSWUG/Known+Installation+Issues+for+v8.0

since I don't see NCORES defined in my /usr/lsst/eups/lib/eupspkg.sh file, 
nor MAKEFLAGS, and SCONSFLAGS doesn't mention explicitly the number of 
cores to use:
export SCONSFLAGS=${SCONSFLAGS:-"opt=3"}


Thanks,
--dustin