On the Performance Impact of Data Access Middleware for NoSQL Data Stores A Study of the Trade-Off between Performance and Migration Cost.

The last few years have seen a drastic increase in the amount and the heterogeneity of NoSQL data stores. Consequently, exploration and comparison of these data stores have become difficult. Once chosen, it is hard to migrate to different data stores. Recently, a number of data access middleware platforms for NoSQL have emerged that provide access to different NoSQL data stores from standardized APIs. However, there are two key concerns related to: (i) the performance overhead introduced by these platforms, and (ii) the effort required to migrate between different data stores. In this paper, we present two complementary studies that provide answers to the above mentioned concerns for three of the most mature data access middleware platforms: Impetus Kundera, Playorm, and Spring Data. First, we evaluate the performance overhead introduced by these platforms for the CRUD operations. Second, we compare the cost of migration with and without these platforms. Our study shows that, despite their similarity in design, these platforms are still substantially different performance-wise. Both studies are complementary as they show the trade-off inherent in adopting a data access middleware platform for NoSQL: by allowing some performance overhead, the developer gain benefits in terms of portability and easy migration across heterogeneous data stores.