||Oracle Tips by Burleson
Oracle10g Grid Computing
Chapter 12 - RAC Design Considerations
Identifying Extent Management Issues
If the “row
cache lock” event is a significant contributor to the non-idle wait
time in v$system_event, then there
is contention in the data dictionary cache. Extent allocation and
de-allocation operations could cause this. v$rowcache provides
data dictionary cache information for dc_used_extents
dc_free_extents. This is
particularly true when the values for dlm_conflicts for those
parameters increase significantly over time. This means that excessive
extent management activity is occurring.
Minimizing Extent Management Operations
storage parameter configuration for tables, indexes, temporary
segments, and rollback segments decreases extent allocation and
de-allocation frequency. Do this using the initial, next, pctincrease,
minextents, and optimal parameters.
Using Locally Managed Tablespaces
allocation and de-allocation overhead can be greatly reduced if
locally managed tablespaces are used. For optimal performance and the
most efficient use of space, segments in locally managed tablespaces
should ideally have similar space allocation characteristics. This
enables the tablespace to be created with the proper uniform extent
size that corresponds to the ideal extent size increment calculated
for the segments.
For more information,
see the book
Grid and Real Application Clusters 30% off if you
buy it directly from Rampant TechPress .
Written by top Oracle
experts, this RAC book has a complete online code depot with
ready to use RAC scripts.
can offer world-class remote Oracle database support at super-affordable prices.
Oracle DBA service provides 100% of the remote Oracle database administration
needs for your company, and includes 24x7 access to our staff of 100% OCP
Certified Oracle DBAs.
We require a 12 month service commitment and include the following services:
- Initial configuration review and problem identification
- Installation of Oracle statistics collection mechanisms and quarterly
database growth summaries
- Hourly monitoring of your Oracle database for pending problems
- Periodic performance analysis & identification of tuning activities
- Twenty Four hour Oracle emergency support
- Reporting and resolving all serious Oracle alert log messages
- Free use of the BC
- Quick response emergency support for production database outages
- Four hours of free remote DBA support every month. You can use these free
hours for any DBA activity, including database analysis, system design,
production migrations or personal mentoring.
information, please visit www.oracle-training.cc.