Trace Logic enables you to step forward or backward through a sequence of activities to focus on predecessor/successor relationships. You can use Trace Logic to determine why an activity is scheduled at a particular time, answering questions such as: Were any of its predecessors delayed? Do any of its predecessors or successors have an obsolete constraint? Are two activities currently linked finish to start that should be linked start to start? Why is there negative float?
Where can I do this?
In the activity table of the Projects > Activities page, right-click an activity and select Trace Logic from the activity menu. The Trace Logic dialog box displays.
To display the Activities page, open the project or group of projects you want to work with in the Projects section, then click on the Projects toolbar.
When working with Trace Logic, you can:
Analyze activity relationships in Trace Logic
To analyze predecessor and successor relationships for an activity, select the activity you want to analyze in the Activity Table. In Trace Logic, the activity you selected displays as a box with a blue border. Activity boxes to the left of the selected activity are predecessors. Activity boxes to the right of the selected activity are successors. Activity boxes with a red border represent critical activities.
How do I identify critical activities, critical relationships, and driving relationships?
The following visual indicators represent critical activities, critical relationships, and driving relationships:
- Activity boxes outlined in red are critical activities; activity boxes outlined in blue are not critical activities.
- Solid red lines represent critical relationships, while blue lines represent non-critical relationships.
- Solid lines represent driving relationships, while dashed lines represent non-driving relationships.
Tips:
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P6 Web Access identifies activities as critical based on options you specify when you schedule a project. For more information on how to set options for identifying critical activities, see Control which activities are identified as critical.
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P6 Web Access identifies relationships as driving when all of the following are true: 1) the successor activity has Free Float less than or equal to zero; 2) the activity does not have a Start On or Finish On constraint; and, 3) the activity does not have an Actual Finish date.
Customizing Trace Logic
To change the size of the Trace Logic pane, drag the divider bar between the top and bottom sections of the page.
To move the group of activity boxes around in the Trace Logic pane, click on the toolbar of the Trace Logic dialog box. This is useful when you want to focus on one area of a large group of related activities. When you move the activity boxes, all of the boxes move as a whole; you cannot move individual boxes or sections of the activity path.
To specify the maximum number of predecessors and successors that display in Trace Logic, click on the toolbar of the Trace Logic dialog box. In the Trace Logic Options dialog, enter or select the maximum number (between zero and 2000) of predecessor and successor activities you want to display, then click OK.
To zoom in or out of the Trace Logic display, use the following icons:
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Click to zoom in. You can zoom in an unlimited number of times. |
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Click to zoom out. You can zoom out an unlimited number of times. |
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Click to fit the entire activity path into the available space in the Trace Logic pane. |
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Click to return the Trace Logic display to its normal size. |
Print a Trace Logic layout
Printing features, including page setup and print preview, are available on the toolbar of the Trace Logic dialog box.
To print the current Trace Logic layout, click on the toolbar of the Trace Logic dialog box. Set print options, then click OK.
To change your page settings
- On the toolbar of the Trace Logic dialog box, click
.
- Click the Page Layout tab to set options for page orientation, size, and margins.
- Click the Header/Footer tab to specify header and footer information. In the Header/Footer list, select a default header or footer; or, click Custom Header or Custom Footer to create your own header or footer.
- On the Sheet tab, specify the print area, set scaling options, and choose the page order (top to bottom or left to right).
To view a print preview, click on the toolbar of the Trace Logic dialog box. In the Print Preview window, mark or clear the Margins checkbox to include or exclude margins on the page. To change your page settings, click Setup. To print the layout, click Print.