A parallel model for SQL astronomical databases based on solid state storage

作者：Gonzalez Nunez J^*; Gutierrez Sanchez R; Salgado J; Segovia J C; Merin B; Aguado Agelet F

来源：Astronomy and Computing, 2017, 20: 77-82.

DOI：10.1016/j.ascom.2017.03.006

• Gaia Databases
• SQL
• PostgreSQL

Query planning and optimisation algorithms in most popular relational databases were developed at the times hard disk drives were the only storage technology available. The advent of higher parallel random access capacity devices, such as solid state disks, opens up the way for intra-machine parallel computing over large datasets.
We describe a two phase parallel model for the implementation of heavy analytical processes in single instance PostgreSQL astronomical databases. This model is particularised to fulfil two frequent astronomical problems, density maps and crossmatch computation with Quad Tree Cube (Q3C) indexes. They are implemented as part of the relational databases infrastructure for the Gaia Archive and performance is assessed.
Improvement of a factor 28.40 in comparison to sequential execution is observed in the reference implementation for a histogram computation. Speedup ratios of 3.7 and 4.0 are attained for the reference positional crossmatches considered. We observe large performance enhancements over sequential execution for both CPU and disk access intensive computations, suggesting these methods might be useful with the growing data volumes in Astronomy.

• 出版日期2017-7