5
Chapter
How to Improve Performance
In This Chapter .................... 5-3
Disk Layout ..................... 5-4
Optimize Blobspace Blobpage Size ............. 5-5
tbcheck -pB and tbcheck -pe Utility Commands ....... 5-5
Blobpage Average Fullness............... 5-7
Apply Effective Criteria................ 5-8
Eliminate User-Created Resource Bottlenecks.......... 5-8
When Is Tuning Needed?................. 5-10
% Cached Fields .................. 5-10
ovtbls, ovlock, ovuser, and ovbuff Fields .......... 5-11
Bufsize Pages/IO Fields................ 5-11
Shared-Memory Buffers ................. 5-13
When Is Tuning Necessary? .............. 5-13
How Is Tuning Done? ................ 5-13
Shared-Memory Resources ................ 5-14
When Is Tuning Necessary? .............. 5-14
How Is Tuning Done? ................ 5-15
Log Buffer Size .................... 5-15
Logging Status ................... 5-15
How Is Tuning Done? ................ 5-16
Page-Cleaner Parameters................. 5-17
Ef��cient Page Cleaning ................ 5-17
How Is Tuning Done? ................ 5-19