JEPSEN

FaunaDB 2.5.4

2019-03-04

Fauna and Jepsen worked together to identify 19 issues in FaunaDB, a distributed transactional document store based on the Calvin protocol. In addition to minor problems with schema changes and availability, we found that indices could fail to return negative integer values, skip records at the end of pages, and exhibit read skew. Temporal queries could observe older states than the timestamp they requested, and exhibited occasional read skew. We also found nonmonotonic reads, long fork, and read skew in development releases. We found that basic key-value operations in FaunaDB 2.5.4 appeared to provide snapshot isolation up to strict serializability, depending on workload. FaunaDB has addressed every serious issue we identified in version 2.6.0, and fixes for minor issues, like concurrent schema modification, are slated for upcoming releases.