This topic explains how to view statistics in the Visual Statistics Display (VSD) for use with VMware Tanzu GemFire.
Select statistics and view them using chart templates and customized charts.
Statistic Levels
Each statistic has a characteristic called a level that reflects the amount of background knowledge that you would need to use the statistic with understanding. You can set up VSD to list (in its main window and in associated charts) only those statistics that are at, or below, a certain level of complexity — common, advanced, or wizard.
To establish the levels of statistics that you want to display in VSD, choose the menu item Main > Statistic Level in the main VSD window.
Select Statistics for Viewing
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In the VSD list, click the left mouse button to select the entity or entities you want to view.
- Search for a specific session name or process ID. To find a specific entity, click the mouse in the process list, then press Ctrl-S. When the dialog box appears, enter the PID or name of the entity that you are looking for. VSD highlights the first entity with that PID or name. To find the next match, press Ctrl-S again. To select the highlighted item, click on it. When you have finished, press Return.
- Select all entities or by statistic or by type. Statistics are available for various entities, which are listed under the heading Type in the process list.
Note: You can use the right mouse button to perform these functions:
- Combine multiple entities into a single line. This can be helpful. For example, if you want to measure page reads per second for several hundred entities, you could select all the entities, then combine them into a single line in the chart, thus rendering the data much more readable.
- Combine multiple entities from different files into a single line.
- Eliminate flatlines — entities whose values are always zero.
- Select Single File mode so only one loaded file can be enabled at a time.
- Select for created lines to have absolute timestamps, which is useful when merging files.
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Select a statistic for viewing from the statistics list just below the process list.
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With the selecting statistic, do one of the following:
- To display the statistic in a new chart, type the name of the chart in the Chart entry box, then click New Chart. (Note: If you do not explicitly specify a chart name, VSD will assign one for you.)
- To display the statistic in an existing chart, select the chart name in the Chart entry box. Then click on Add Line.
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To add another statistic to the chart, repeat steps 1 through 3.
Using VSD Chart Templates
VSD templates let you quickly add a set of lines to a chart. Templates are helpful if you find yourself performing the same task frequently in VSD — for example, monitoring the same five or six statistics. By creating a template for the statistics that you want to monitor most frequently, you can automate the task of building charts.
In your template, you can assign a filter for each statistic, to determine how much information is displayed for that statistic. You can also restrict the template to look for extreme conditions (for example, processes that are consuming 90% or more of the CPU).
VSD is shipped with a set of predefined templates, which are maintained in the .vsdtemplates file in your home directory.
| Task | Procedure |
|---|---|
| Create a new chart from a template | In the VSD main window, choose the menu item Template > New Template Chart. This is a good way to display some of the more useful system statistics. |
| Apply a template to the chart you are viewing | In the Chart window, choose the menu item Chart > Add From Template. (Note: If you have zoomed in on a chart, the template filter is only applied to values within the zoomed range.) |
Re-read the .vsdtemplates template file into VSD after you edit it. |
In the VSD main window, choose the menu item Template > Reload Template File. |
| Save the current chart as a template | In the Chart window, configure the chart as you desire, then choose the menu item Chart > Save Template. The template is saved to the .vsdtemplates file. If you save the current chart as a template, you may still need to edit the .vsdtemplates file so that you can give it a more useful name and make the information and patterns it captures more general. |
Chart Menu (Chart Window)
To customize the way VSD displays statistics in your chart, you can choose items from the Chart window’s Chart menu.
| Chart Menu Item | Effect |
|---|---|
| Add from Template | Expand template and add resulting lines to chart. |
| Save Template | Save all lines on chart as a template. |
| Paste | Paste last item on clipboard. |
| Print chart. | |
| Snapshot | Write this chart as a graphic to snapshot.gif. |
| Help … | Open Help window. |
| Zoom In | Zoom in to improve your view of the chart. After you choose this menu item, click to select one corner of the area that you want to zoom. Move the mouse pointer to the opposite corner of the zoom area, then click again. If you have a middle mouse button, you can quickly zoom in on an area by clicking the middle mouse button over it. |
| Zoom Out | Zoom out by using the menu button or by right-clicking in the chart window. |
| Compare Two Points | Log information by comparing two points. |
| Compute Scale All, Unscale All | Adjust the scale of the chart. This helps you view multiple statistics on the same axis. |
| Show Legend | Display the legend for this chart. |
| Time Format | Change the format of the time displayed along the X axis. |
| Show Time Axis Title, Show Left Axis Title, Show Right Axis Title | Display the title alongside the respective axes. |
| Show Current Values | Display the current X and Y values for the selected line at the top of the chart |
| Show Min and Max | Display the minimum and maximum values for the selected line at the top of the chart. |
| Show Line Stats | Display these statistics for the selected line: the number of data samples, the min, max, mean, and standard deviation. The statistics are calculated from all of the data points on the selected line in the region defined by the graph’s current X axis. (To change the region, select Zoom In or Zoom Out from the Chart menu.) |
| Show CrossHairs | Draw cross hairs on graph of item. |
| Show Grid Lines | Draw grid line on graph of item. |
| Close | Close chart window. |
For additional information about the Chart window, choose Help from the Chart menu.
Line Menu (Chart Window)
Customize your VSD chart display using items from the Line menu (in the Chart window). Line menu commands operate on the currently selected line. To select a line, click on it or on its entry in the chart legend. VSD highlights the selected line.
| Line Menu Item | Effect |
|---|---|
| Log Info | Display a log file showing the line statistics for all data samples in the region defined by the graph’s current X axis. |
| Log Delta | Measure the difference between two values on the selected line. Select the line before choosing this menu item then click on the two points whose difference you want to compute. VSD responds by displaying a log file showing the difference in time and value between the two points; the number of data samples in the selected line segment; and the min, max, mean, and standard deviation of those samples. |
| Compute Scale | Compute a scale value for the selected line that will make it visible on the current chart. You can also use the Scale entry box to manually change the scale. The default scale value is 1. |
| Unscale | Reverse the effect of Compute Scale. |
| Graph on Left Axis | Display the Y axis for the selected line to the left of the chart. Otherwise, the Y axis is displayed to the right. You can use this to view multiple lines on the same chart, by graphing large values on one axis and small values on the opposite axis. |
| Symbol | Select a new symbol. |
| Style | Select a line style for connecting points: linear (default), step, natural, quadratic. |
| Update | Update files used by current line. |
| Add Lines | Add a line to the current line. |
| Diff Lines | Remove a line from the current line. |
| Divide Lines | Divide current line by another line. |
| Normalize | Normalize current line. |
| Trim Left, Right | Trim line to left or right of a data point. |
| Untrim Left, Right | Undo any trim line operations. |
| Copy | Copy current line to clipboard. |
| Cut | Cut current line to clipboard. |
| Delete | Remove the selected line from this chart. |
Customizing Your VSD Chart
You can customize and manipulate a VSD chart in many ways:
- To select a line in the chart, click on it or on its entry in the chart legend.
- To delete a line from the chart, click the middle mouse button (if available) on its entry in the chart legend. Alternatively, select the line’s entry in the chart legend and choose Line > Delete.
- To find out about a specific point in a chart, hold the mouse pointer over it.
View Statistic Information
To view a description of the most recently selected statistic, along with information about its type, level, and default filter, go to the VSD main window, then choose the menu item Main > Show Statistic Info.
In the Statistic Information window, you can redefine the level and default filter for any VSD statistic.
- The statistic’s level — common, advanced, or wizard — allows you to determine whether the statistic is displayed in the VSD statistic list.
- Whenever you add a line to a chart, the filter determines how information is displayed for the selected statistic.
| Default Filter | Effect |
|---|---|
| Default | No Filter if the statistic represents a snapshot of a value. PerSecond if the statistic represents a value that always increases. |
| No Filter | Display the raw values for the statistic with no filtering. |
| PerSample | Display the difference between two consecutive samples of the statistic. |
| PerSecond | Display the difference between two consecutive samples of the statistic, divided by the number of elapsed seconds between the two samples. |
| Aggregate | Display a running total of per-sample deltas for the statistic. Reset to zero when the delta is zero or changes direction. |
Once you have added the line to a chart, you can override its default filter by specifying a new filter from the drop-down menu at the top of the Chart window.
If you leave the Statistic Information window up as you work, it changes to reflect the current statistic. In this way, you can get a quick explanation of any statistic that you are currently examining.
