Performance Improvements

[DerekStride]

Related to: #5

Adding a cache works great for development where rebuilding the graphviz files happens on every change. This will allow a user to tweak and update graphs and have the changes take effect. However, the performance hit is maximized on startup or when building in production.

There are a few strategies we can use to alleviate these issues:

1. Startup performance

To tackle better startup performance we can use a level 2 cache. We can use a temporary file to cache changes to the filesystem which can be reused between sessions.

2. Production performance

Having the graphviz files around is great for version controlling the graphs. However, at some point we may want to convert these files directly into images and persist them so we don't incur the performance hit at build time in our production environment.

We can use the converter file in a command plugin to enable converting graphs into static images.

bundle exec jekyll graphviz convert --files FILE1[,FILE2[,FILE3...]] --format svg