Tuning Adaptive Server Enterprise for performance can involve several processes in analyzing the “Why?” of slow performance, contention, optimizing and usage.
The Optimizer in the Adaptive Server takes a query and finds the best way to execute it. The optimization is done based on the statistics for a database or table. The optimized plan stays in effect until the statistics are updated or the query changes. You can update the statistics on the entire table or by sampling on a percentage of the data.
This volumn from the series on Performance and Tuning covers the information on optimizing in Adaptive Server.
The remaining manuals for the Performance and Tuning Series are:
Performance and Tuning: Basics
This manual covers the basics for understanding and investigating performance questions in Adaptive Server. It guides you in how to look for the places that may be impeding performance.
Performance and Tuning: Locking
Adaptive Server locks the tables, data pages, or data rows currently used by active transactions by locking them. Locking is a concurrency control mechanism: it ensures the consistency of data within and across transactions. Locking is needed in a multiuser environment, since several users may be working with the same data at the same time.
Performance and Tuning: Abstract Plans
Adaptive Server can generate an abstract plan for a query, and save the text and its associated abstract plan in the sysqueryplans system table. Abstract plans provide an alternative to options that must be specified in the batch or query in order to influence optimizer decisions. Using abstract plans, you can influence the optimization of a SQL statement without having to modify the statement syntax.
Performance and Tuning: Monitoring and Analyzing for Performance
Adaptive Server employs reports for monitoring the server. This manual explains how statistics are obtained and used for monitoring and optimizing. The stored procedure sp_sysmon produces a large report that shows the performance in Adaptive Server.
You can also use the Sybase Monitor in Sybase Central for realtime information on the status of the server.
Each of the manuals has been set up to cover specific information that may be used by the system administrator and the database administrator.
