[Pkg-scicomp-devel] Bug#571322: [atlas] custom build improvements

[Adrian Benson]

Package: atlas
Version: 3.8.3-9

Hi Sylvestre

Sorry about the delay in submitting these.

1.  There needs to be a way of incrementing the version for custom builds
otherwise the custom build will be superseded by the generic versions in
the repo. I changed  debian/rules:|custom-stamp| and it seems to work.

|
custom-stamp:
         rm -f configure-stamp
         # Here, the trick is pretty simple:
         # * We don't want to build all the optimized version of Atlas. 
Just the
         #   one for the current CPU
         # * We override ARCHS by base__
         # * Base is the name of the package (libatlas3gf-base)
         # * __ is provided to have the right expression
         # * the regexp will consider that atlasArch and atlasISA are empty
         #   therefor, leaving the choice of the optimization to Atlas
         # * After that, we fall back to the normal build procedure by 
calling
         #   debian/rules itself (yep, recursively)

         # incerment version with a local suffix to prevent custom 
package being
         # superseded and clobbered by the generic pre-built atlas 
packages that
         dch -U --local='+custom'  "custom build on `uname -a`"

         # Remove all the other archs in this case

         sed '/AFTER THAT/q' $(CURDIR)/debian/control.in > 
$(CURDIR)/debian/control
         debian/rules ARCHS=base__ binary
         touch $@|

2.  Atlas timing needs th cpu clock to be set to the maximum - dynamic 
frequency mechanisms
should be disabled.  So you need to add 'cpufrequtils' as a build 
dependency for custom builds.
There should then be a check using 'cpufreq-info' to make sure the cpu 
governer is set to
'performance'. Not much of a makefile programmer, but a bash style test 
would be:

|ncpu=$(cpufreq-info | grep "analyzing CPU" -c)

||for (( cpu=0 ; cpu < $ncpu ; cpu++)); do
     if [ -z "$(cpufreq-info -p -c $cpu | grep performance)" ]; then
         echo "frequency governor on cpu=$cpu is not set to 'performance'
         echo "run: 'sudo cpufreq-set -g governor -c cpu#' for each cpu"
         echo "aborting atlas build"
         exit (1)
|        fi
done


Adrian