The Instance Main window provides a big picture about the state of the Oracle instance and how it has been in the recent past. It is a convenient place to start exploring server activity. Once a particular area of interest is identified, you can jump to the detailed screen using the drill-down feature.
The Instance Main window has a special status. When you make a new connection to the Oracle instance, this window is created and opened. It also means that a new Lab128 Instance monitor has been opened. The Instance monitor is represented by the Main window and set of child windows all collecting and providing data about same Oracle instance. If you close the Instance Main window, the connection to the instance will be closed, all child windows will be closed too. All internal structures for this Instance monitor will be also released.
There are many graphs on the Main window, each of them representing a performance statistic. There are two graphs in the Main window in the lower left corner that can be changed to any of the predefined statistics. Choose the statistic from the drop-down list above the graph.
There are several tabular views in the Main Window. The most important one is the Top Wait Events. It shows current wait events sorted by 'time waited' in descending order. The events with a wait time of less than 1% are not shown. The idle events are not shown, unless the check box "Include Idle" on top of this view is checked.
Other tabular views provide quick high level information about Tablespaces and their utilization, Transactions and Undo / Rollback usage, Temporary tablespace usage.
You can open a window with detailed information about a particular area using hot spots. The following picture shows all hot spots / shortcuts in the Main window:
Click on any of these hot spots to open another window. As an alternative, use the Main menu, View item to call all mentioned detail windows.
Some additional actions and options can be performed through the pop-up menus, which are opened by right-clicking on certain areas. All graphs and tabular views in the Main window have popup menus. The name of the database also has a pop-up menu:
There are following options in this pop-up menu:
Lab128 provides the opportunity to explore activity history by scrolling back in time using the scroll bar at the bottom of the window. When scrolling, a time window appears showing the time. All information in the Main window updates correspondingly, showing values effective at the indicated time. The length of history that can be scrolled back depends on the Data History Length value in Settings for Monitored Instance.
The status bar in the bottom of the Main window provides some basic information about the connection to Oracle used by Lab128:
SID, serial#, name of the instance and the host name, instance start time.
It also displays the system time of your workstation and the system time of the Oracle server.
Note: for consistency with all other Oracle information, all statistics use the server time, not the local time of workstation. When referring to current time in this manual, you should assume Oracle server current time. By default, server time is shown in the time zone of the server. Optionally, you can select the time zone of the workstation or UTC / GMT (see also Show Time in Time Zone setting).
The last item in the status bar is not related directly to Oracle: it is the Lab128 internal queue length of performance queries scheduled to run on Oracle. Normally it should be close to 0. If so, it means that all queries are executing quickly and there are no pending queries. This is an indication that Lab128 and Oracle are working in harmony: the whole data gathering process is running smoothly and efficiently. This harmony may be broken for a number of reasons: a network slowdown, the Oracle instance being slow to process even basic queries, etc. Although Lab128 Queue length is not directly related to the performance of the Oracle instance, it may be useful for the detection of ongoing problems.