Data sources

• The API system is asynchronous. Some delay in the response is normal and expected.

• Each method has a data source indicating where the data is coming from, and thus how up-to-date it is.

Data Source	Latency	Description
Matching Engine	lowest	The Matching Engine produces the response directly
Memory	low	Data is fetched from API server's local or external memory cache
Database	moderate	Data is retrieved from the database

• Some methods have more than one data source (e.g., Memory => Database).

  This means that the API will look for the latest data in that order: first in the cache, then in the database.