How to Improve Performance 5-3
In This Chapter
With each OnLine release, Informix engineers incorporate new code that
increases processing efficiency, reduces overhead, and improves perfor-
mance. This effort to tune the OnLine code has two consequences for you:
■The OnLine database server runs faster.
■OnLine administration requires less performance tuning.
The information in this chapter assumes that your application has been
writtenas efficiently as possible. (Refer to IBM Informix Guide to SQL: Tutorial.)
Performance gains from tuning are not dramatic, since code enhancements
havebuilt performance gains directly into the IBM Informix OnLine product.
However, incremental benefits can be realized with careful adjustments
tailored to your specific environment.
Inthis OnLine release, you gain the greatest improvements in performance if
you focus your attention on managing disk space layout and eliminating
problems that are unintentionally created by users. The guidelines that you
shouldfollow are clear-cut and easy to apply, regardless of your application
design. Three topics fall into this first tier of performance issues:
■Placing databases, tables, and logs on disk (page 5-4)
■Optimizing blobspace blobpage size (page 5-5)
■Eliminating user-created resource bottlenecks (page5-8)
The second tier of performance improvements falls into the more abstract
categoryof performance tuning. Tuning guidelines vary,depending both on
your hardware and your application. Trade-offs arise that you alone can
evaluate, based on your environment. Informix can describe the reasons for
the trade-offs and the possible advantages of different tunings; however, it
remains your responsibility to consider the needs and desires of your users
and to select the correct approach.