A speed-up trick for dot performance testing

If you are

  • testing dot with large, slow input files
  • using some combination of nslimit mclimit remincross searchsize to speed up the test and make it tolerable (e.g. dot 2854_0.gv -Tsvg -v -Gnslimit=2 -Gmclimit=.22 -Gremincross=false -Gsearchsize=20 -o2854_0.true.svg)

try setting splines=false

your job will probably run faster and maybe much faster.

Why? dot can sometimes thrash about while trying to draw splines if the previous phases are tightly limited