ept/hermitage resource
What are the differences between the transaction isolation levels in databases? This is a suite of test cases which differentiate isolation levels. observed · 2026-08-28
Health v2 · maintenance only
61/100
- Activity 63
- Release rhythm 35
- Longevity 100
Flags: no_releases no_license
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: n/a
- age_days: 4318
- days_rel: n/a
- days_push: 222
- n_releases_24m: 0
Adoption not part of the score
2743 stars · 195 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded
Hermitage is a suite of test cases that probes how different database systems actually implement their transaction isolation levels, simulating concurrency anomalies like write skew and phantom reads. It documents results for PostgreSQL, MySQL/InnoDB, Oracle, SQL Server, FoundationDB, CockroachDB, YugabyteDB, and Memgraph.
Use cases
- compare transaction isolation levels across databases
- find out what 'repeatable read' actually means in Postgres vs MySQL
- test whether a database prevents write skew
- verify concurrency anomaly behavior before choosing an isolation level
- learn about weak isolation and race conditions in ACID databases
- port isolation tests to a new database system
When to choose
- you need to understand the real guarantees behind a database's advertised isolation levels
- you're designing systems that depend on transactional concurrency behavior
- you're researching or teaching database isolation and ACID semantics
When to avoid
- you need an automated CI test framework for your application
- you want a general-purpose database benchmark for performance
- your database isn't covered and you can't port the tests yourself
Facets
dataset · maturity maintenance
testing database benchmarking databases testing microservices developer-tools cross-platform transaction-isolation acid concurrency-anomalies test-suite database-internals
3 sources
- readme: https://github.com/ept/hermitage · fetched 2026-08-28 · 41b272d8b8d7
- homepage: http://martin.kleppmann.com/2014/11/25/hermitage-testing-the-i-in-acid.html · fetched 2026-08-29 · af24a7f29fd7
- site_page: https://martin.kleppmann.com/contact.html · fetched 2026-08-29 · 8469a858e30f
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| ept/hermitage | main | 61 |
For agents
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem