The Data Accelerator is a proprietary development of 1C, designed to speed up the processing of large amounts of data used for analytical reports. Basically, it is a special database management system (DBMS), in which the data is entirely placed in the server's RAM (in-memory DB) for processing. At that data is stored in structures optimized for analytical reports. The Data Accelerator runs as a service within a 1C:Enterprise server cluster and works only in combination with the Database Copy mechanism.
The Data Accelerator is optimized for analytic queries that process large amounts of data and return a relatively small number of records. This is the recommended use case for the mechanism. Building business intelligence systems for operational data analysis requires joint use of the Data Accelerator and 1C:Analytics products.
The platform can take advantage of multiple data accelerators on a single database, distributing the load among them. For instance, you can randomly send user requests to any of the available data accelerators or separate reports into groups and specify which accelerator should process each group.