The answer of the author. I tried two things: spork plug-in and in-memory database. My dev configuration: Ubuntu VirtualBox hosted on Win7, Ruby 1.8.7, Rails 3, SQLite.
Spork 35 2 . , github readme. , Guard spork .
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RVM Ruby 1.8.7 1.9.2. 58 42 .
: Spork 1.8.7 1.9.2 TDD.