lots of "Read from postgres only" logs after upgrading to 2.93.6

[shawnzhu]

in a self-hosted langfuse prior to 2.80.x, I recently upgraded it to 2.93.6 with a smooth db migration, Thank you for making upgrade so easy!

I noticed that there're lots of logs with msg Read from postgres only. then I tracked down to web/src/server/utils/checkClickhouseAccess.ts and it seems harmless. However, I used this environment variable to avoid this log entry:

LANGFUSE_EXPERIMENT_EXCLUDED_OPERATIONS=traces.hasAny,traces.all,traces.countAll,traces.metrics,traces.filterOptions,scores.all,scores.countAll,scores.filterOptions,sessions.all,sessions.countAll,sessions.filterOptions,sessions.byId,users.all,users.metrics,users.byId,generations.all,generations.countAll,datasets.runsByDatasetId,datasets.runitemsByRunIdOrItemId,prompts.metrics,prompts.versionMetrics,api/public/traces/[traceId],api/public/observations/[observationId],api/public/observations,api/public/scores/[scoreId],scores.countAll

Since I already have LANGFUSE_ENABLE_EXPERIMENTAL_FEATURES=false, so I assume the above one should be harmless. However, I still want to share this to learn any possible side-effects.

[dosubot[bot]]

The "Read from postgres only" log message indicates that the system is configured to read data exclusively from the PostgreSQL database under certain conditions. This can happen if the environment variable LANGFUSE_READ_FROM_POSTGRES_ONLY is set to "true", or if specific operations are excluded from using Clickhouse due to feature flags or project exclusions ^[1].

In your case, setting LANGFUSE_EXPERIMENT_EXCLUDED_OPERATIONS with a list of operations means those operations will default to using PostgreSQL instead of Clickhouse. This is expected behavior and should be harmless as long as you are aware that these operations will not utilize Clickhouse for data reads ^[1].

Since you have LANGFUSE_ENABLE_EXPERIMENTAL_FEATURES=false, it should not interfere with the excluded operations list, and there should be no side effects from this configuration. However, it's always good to monitor your application's performance and behavior to ensure everything operates as expected.

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other}

[marcklingen]

These are logs that were added in the final versions of langfuse 2.x as they included some feature flagged implementations for langfuse v3.x

You should be able to hide them via LANGFUSE_LOG_LEVEL, docs here.

Sorry for the verbose logs, these are removed in v3 afaik.