Performance Page
To open the Performance Page
- Select the Spotlight on Oracle connection in the Spotlight Browser.
-
Click Tuning | Performance.
Overall Instance Response Time Chart
This shows the overall response time for the specified operations in the current Oracle instance. The response times that make up the overall response time are:
| Data | Description |
|---|---|
|
Parse Time |
The time taken to prepare SQL statements for execution against the Oracle database. |
|
Latch Wait Time |
The time taken for a session to acquire a latch that is held by another session. |
|
Direct Read Time |
The time taken to read data directly from disk, bypassing the buffer cache. |
|
Direct Write Time |
The time taken to write data directly to disk, bypassing the buffer cache. |
|
Physical Read Time |
The time taken to read blocks of data from disk to the SGA. |
|
Physical Write Time |
The time taken to write modified blocks from the SGA to disk by the DBWR processes. |
|
CPU Time |
The rate of CPU time used by the database. Note: Available for Oracle 10g and later. |
|
Other Time |
(Oracle 10g and later) This is the sum of DB time and background elapsed time excluding those series shown on the chart. |
Memory Allocation History Chart
Note: Available for Oracle 10g and later.
Memory History shows all recent changes to memory allocation in the current Oracle instance. The chart contains data series for these memory components:
| Data | Description |
|---|---|
|
Buffer cache |
An area in the SGA (System Global Area) that contains copies of blocks from database files. The buffer cache exists primarily to reduce disk I/O. |
|
Large pool |
The Large pool shows the size of the large pool allocation heap, which can be used by parallel execution and backup processes, and session memory for MTS sessions. Note: If the Large pool is not configured, these large memory requests are redirected to use the Shared pool. |
|
Other |
All memory components not already covered by another category. (Java pool, for example.) |
|
PGA |
Program Global Area. A dynamic area of memory that stores data and control information for a dedicated Oracle server process or background process. |
|
Shared pool |
The Shared pool caches SQL statements, PL/SQL programs, and object definitions. |