🧞Data cache

Toucan offers robust data caching mechanisms to enhance performance and responsiveness. This documentation provides an in-depth overview of the data caching features implemented in both the frontend (user's browser level) and backend (Toucan server level).

Frontend data caching

The frontend data caching takes place within the user's web browser. This cache ensures that once a data request is made by a browser during a "session", it will not be repeated until the user refresh the page or quit Toucan (and comeback to it).

This cache feature is enabled by default.

Backend data caching

The backend data caching takes place within Toucan backend server.

Slow query caching

This is designed to cache server-side queries made via connectors in live data. If a query is slow (exceeding a certain amount of time defined by the parameter TOUCAN_QUERY_CACHE_MIN_TIME), it is cached and will not be rerun if another client requires the same data.

The parameter TOUCAN_QUERY_CACHE_MIN_TIME is set as 1000 ms by default.

Cache lifetime

The cache lifetime is equals by default to 10 minutes.

The duration is configurable at the connector, and query levels (for some connectors), within the field "Slow queries' cache expiration time."

Amount of data limits

The maximum total amount of data cached cannot exceed 2GB. When exceeding this limit, the data are not cached anymore.

The maximum amount of data for a specific query cannot exceed 200MB, otherwise the data is not cached.

Data preparation (YouPrep) caching

There is a specific cache that is used when making data preparation with YouPrep. This cache is applied only on Toucan execution engine, and not when evolving within a NativeSQL context.

The first step within YouPrep (aka Source step) is always kept in cache, and then when any following step takes more than 3 sec to be completed, the result is also cached in order to ensure a fluid experience within YouPrep.

Cache lifetime

The cache is deleted once dataset edition interface is closed.

You knows now everything on data caching system.