tailieunhanh - Tuning Database Configuration Parameters with iTuned

The universal UDF SAS_JOB represents a complex multi-step process that calls into all the SAS In-Database subsystems that can reside in the DBMS: formats (TKFORMAT subsystem), data transformation and model scoring (TKFUNCTIONS and TSPL subsystems), and analytics (TKSCIENCE subsystem). Both SAS clients and DBMS clients can use the integrated SAS servers. A SAS client communicates directly with the SAS servers deployed on the DBMS head node. The SAS client can execute SAS jobs inside the DBMS by sending commands to the SAS servers that are running on the DBMS head nodes. When these SAS jobs reference SAS formats,. | Tuning Database Configuration Parameters with iTuned Songyun Duan Vamsidhar Thummala Shivnath Babu Department of Computer Science Duke University Durham North Carolina USA syduan vamsi shivnath @ ABSTRACT Database systems have a large number of configuration parameters that control memory distribution I O optimization costing of query plans parallelism many aspects of logging recovery and other behavior. Regular users and even expert database administrators struggle to tune these parameters for good performance. The wave of research on improving database manageability has largely overlooked this problem which turns out to be hard to solve. We describe iTuned a tool that automates the task of identifying good settings for database configuration parameters. iTuned has three novel features i a technique called Adaptive Sampling that proactively brings in appropriate data through planned experiments to find high-impact parameters and high-performance parameter settings ii an executor that supports online experiments in production database environments through a cycle-stealing paradigm that places near-zero overhead on the production workload and iii portability across different database systems. We show the effectiveness of iTuned through an extensive evaluation based on different types of workloads database systems and usage scenarios. 1. INTRODUCTION Consider the following real-life scenario from a small to medium business SMB enterprise. Amy a Web-server administrator maintains the Web-site of a ticket brokering company that employs eight people. Over the past few days the Web-site has been sluggish. Amy collects monitoring data and tracks the problem down to poor performance of queries issued by the Web server to a backend database. Realizing that the database needs tuning Amy runs the database tuning advisor. SMBs often lack the financial resources to hire full-time database administrators or DBAs. She uses system logs to identify the workload W of .