defkode/activerecord_cache_store — pull request #2 by jrust (2011-12-02 17:35:05+00:00)
Title: Performance Enhancement for ActiveRecordCacheStore

Sorry, one more that I noticed last night. It involves a trade-off of removing the validates_uniqueness constraint on the key, but by removing it one less query per cache write is required. And since the cache store already checks to make sure the entry doesn't exist it seems to make sense.