This started as a question on a MyRocks list. MyRocks comes from MariaDB in this case and the code that determines whether the truncate table fast path is used looks different in MariaDB than in FB MySQL. By "fast path" for truncate I mean the use of drop/recreate for truncate. The slow path is delete one row at a time. In this case, truncate is doing delete one row at a time for MyRocks in MariaDB but drop/recreate in FB MySQL.

https://groups.google.com/forum/#!topic/myrocks-dev/dhweTwN-9xg
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