EnterpriseDB created a framework for benchmarking performance of PostgreSQL
and MongoDB and made it available on Github -
https://github.com/EnterpriseDB/pg_nosql_benchmark
EDB consulted with multiple analysts with expertise on the topic, and they
were not aware of any specific benchmarks for measuring the performance of
PostgreSQL compared to MongoDB.
We’ve created a lightweight tool for the open source community to copy,
modify and try with the hope of creating a standard. We welcome efforts to
replicate our tests that found PostgreSQL outperformed MongoDB and to
develop additional tests, or additional feedback.