middleman/middleman — pull request #648 by bhollis (2012-10-21 04:22:36+00:00)
Title: Make Sitemap::Store more thread-safe.

On the plus side, this correctly locks the sitemap such that other threads don't see a partially updated sitemap. This eliminates the missing images and other bugs that I always see while running preview server.

On the negative side, this also makes Middleman much slower since page loads *have* to wait for the sitemap refresh. My opinion is that we just need to make sitemap refreshing much faster.