Please also see this blog post on tweaking your ruby GC settings. I use and love DatabaseCleaner, although historically I had never paid too much attention on the performance of its varies cleaning strategies - I’d always used truncation. We use Postgres, and after digging around and finding out the difference between DELETE and TRUNCATE, I ended up improving our test suite speed by about 30-40% simply by tweaking the cleaning strategies. RSpec.configure do |config| config.before :su...