Inside the Automatic Workload Repository
In all versions prior to Oracle
Database10g, the v$ views never captured time-series
data. Administrators were forced to take snapshots using
BSTAT-ESTAT or STATSPACK to see the changes over time. Oracle
Database10g introduces new v$ metric tables,
v$eventmetric, v$waitclassmetric and
v$waitclassmetric_history, which keep elapsed-time data.
In 10g, all v$ views that contain
The AWR and ASH Wait Event Tables
Oracle Database 10g has radically changed
the way it captures wait event information. There are a host of
new v$ and wrh$ views related to Oracle wait
events. The list of wait events has been expanded and Oracle
Database 10g now captures statistics on over 800 specific wait
events. The new wait events are a result of separating latch
waits into their individual components and separating enqueue
waits or locks into a finer level of granularity.
The foundation of the new wait event
architecture is called the time model. Oracle has introduced
several important new wait event v$ views in 10g.