Initialization Parameters, 182 of 188

TIMED_STATISTICS

Parameter type:	Boolean
Parameter class:	Dynamic. Scope = `ALTER` `SYSTEM`, `ALTER` `SESSION.`
Default value:	`FALSE`
Range of values:	`TRUE` \| `FALSE`
`TIMED_STATISTICS` specifies whether statistics related to time are collected or not. Appendix C, "Statistics Descriptions", indicates which statistics depend on the setting of this parameter. `TRUE`: The statistics are collected and stored in trace files or displayed in the `V$SESSTATS` and `V$SYSSTATS` dynamic performance views. `FALSE`: The value of all time-related statistics is set to zero. This setting lets Oracle avoid the overhead of requesting the time from the operating system. Normally, `TIMED_STATISTICS` should be `FALSE`.
On some systems with very fast timer access, Oracle might enable timing even if this parameter is set to `FALSE`. On these systems, setting the parameter to `TRUE` can sometimes produce more accurate statistics for long-running operations.
See Also: Oracle8i Designing and Tuning for Performance for more information on setting this parameter and on performance diagnostic tools in general.