Algorithms for the Database Layout Problem

We present a formal analysis of the database layout problem, i.e., the problem of determining how database objects such as tables and indexes are assigned to disk drives. Optimizing this layout has a direct impact on the I/O performance of the entire system. The traditional approach of striping each object across all available disk drives is aimed at optimizing I/O parallelism; however, it is suboptimal when queries co-access two or more database objects, e.g., during a merge join of two tables, due to the increase in random disk seeks. We adopt an existing model, which takes into account both the benefit of I/O parallelism and the overhead due to random disk accesses, in the context of a query workload which includes co-access of database objects. The resulting optimization problem is intractable in general and we employ techniques from approximation algorithms to present provable performance guarantees. We show that while optimally exploiting I/O parallelism alone suggests uniformly...

• Type: Conference
• Year: 2005
• Where: ICDT
• Authors: Gagan Aggarwal, Tomás Feder, Rajeev Motwani, Rina Panigrahy, An Zhu
• Keywords: Database, Disk Drive, I/O Parallelism, ICDT 2005, Random Disk