Is there a way to calculate how long a dot graph will take in graphviz?

Question

Is there any way to calculate how long a dot graph will likely take to render?

I am currently running with 25,000 nodes and 42,000 edges. It's taking some hours and I'd like to know if to give up or get an estimated time when it completes.

Answer 1

Short answer: nope.
Longer answer: There are things you can do to better understand what dot is doing and make it run faster.

• Adding -v4 (https://www.graphviz.org/doc/info/command.html#-v) to the command line will (help) show progress (not well documented) (4 is arbitrary)
• There are 5 or more attributes that you can use to improve performance (mclimit, nslimit, nslimit1, remincross and searchsize) (again, not well documented) As a guess, try setting nslimit and nslimit1 both to 2.

Here are some links to more performance info:

• (Linux:) Logging w/ timestamp: https://forum.graphviz.org/t/how-to-timestamp-dot-fdp-neato-twopi-circo-v-output/654
• https://forum.graphviz.org/t/where-does-generating-the-graph-take-most-of-the-time/668/3
• https://forum.graphviz.org/t/dot-command-seems-to-never-end/958/4
• You might be having a "footprint" problem with all those nodes (Too many square inches of node space) Minimally, set output format to svg.
• Some "innocent" attributes can also be killers, like splines=ortho (https://forum.graphviz.org/t/creating-a-dot-graph-with-thousands-of-nodes/1092)
• (future) https://gitlab.com/graphviz/graphviz/-/issues/2135

25,000 nodes is a fair number of nodes, but 42,000 edges is not that many edges/node
With that many nodes, you might also try some of the other Graphviz engines (neato, fdp, circo, twopi) Often, one or more will run much faster.