development/keystest/cache-bisect.sh

   1 #!/bin/bash
   2
   3 # Cache-bisect is
   4 # roughly based on git-bisect, but uses SVN and caches every build tree
   5 # to maximize performance. The idea here is that if the first few tests
   6 # happen very quickly, and give plausible results, you can have
   7 # confidence that you can just leave it running. Without that confidence
   8 # I'd be continually thinking "Is the bisect still working, maybe I
   9 # should check" so the bisect would be taking up my mental space. With
  10 # cache-bisect, I can fire-and-forget, leaving the CPU to do the menial
  11 # tasks while I think about other things. Additionally caching the
  12 # build-trees cuts down on the amount of bandwidth required on the SVN
  13 # server
  14 #  It uses three levels
  15 #    1) At the bottom level, it bisects much like git-bisect
  16 #    2) At the second level, it bisects, but only over cached revisions.
  17 #    3) The the top level it does what I refer to as a "multisect". The
  18 # idea is that you may not know which revision was a good revision, and
  19 # picking revision 1 as the "good" revision is not only mildly wasteful
  20 # but is likely to produce misleading results. Instead it starts
  21 # stepping backwards, first trying 1.6.0, and then going backwards
  22 # through trunk.
  23
  24         KT=$(cd $(dirname "$0") && pwd)
  25 $KT/cache-bisect.py "$@" | tee out/cache-bisect-$USER.log
  26
  27