Title
Dynamic workload management for very large data warehouses: juggling feathers and bowling balls
Abstract
Workload management for business intelligence (BI) queries poses different challenges than those addressed in the online transaction processing (OLTP) context. The fundamental problem is that the execution times of BI queries can range from milliseconds to hours, and it is difficult to estimate these times accurately. Key challenges raised by this problem are how to identify queries that are not performing properly and what to do about them. We propose here a workload management system for controlling the execution of individual queries based on realistic customer service level objectives. In order to validate our proposal, we have implemented an experimental system that includes a dynamic execution controller that leverages fuzzy logic. We present results from a number of experiments that we ran using workloads based on actual industrial workloads and customer objectives that we gathered by interviewing industry practitioners. Our experiments show that even a handful of moderately mis-behaving problem queries can have a significant impact on a workload consisting of thousands of queries. We were surprised when our experiments also demonstrated that false positives -- incorrectly identifying a normal query as a problem -- can also have significant consequences. For those reasons, it is very important that an execution controller be as accurate as possible -- avoiding both false positives and false negatives. Our experiments also validate that our execution controller can markedly improve the execution of a workload that includes problem queries.
Year
Venue
Keywords
2007
VLDB
execution time,bi query,dynamic workload management,false positive,large data warehouse,mis-behaving problem query,problem query,false negative,fundamental problem,workload management system,dynamic execution controller,execution controller,bowling ball,business intelligence,transaction processing,fuzzy logic,management system
Field
DocType
Citations 
Data warehouse,Data mining,Control theory,Workload,Computer science,Online transaction processing,Fuzzy logic,False positives and false negatives,Business intelligence,Database,False positive paradox
Conference
26
PageRank 
References 
Authors
1.40
16
4
Name
Order
Citations
PageRank
Stefan Krompass118413.15
Harumi Kuno229721.62
Umeshwar Dayal384522538.92
Alfons Kemper43519769.50