The Quantitative Timeline (-> -> ) gives an overview of the parallel behavior of the application. It shows - over time - how many processes or threads are involved in which function. Along the time axis, the different functions are presented as vertically stacked color bars. The height of these bars is proportional to the number of processes that are currently within the respective function.
When the mouse hovers over the Quantitative Timeline, the status bar displays the present position of the cursor with respect to time. It also shows details pertaining to the function group under the cursor. Figure 4-14 shows that the mouse is currently at 2.01171 seconds and that it hovers over MPI.
The Settings dialog box in the Quantitative Timeline has two tabs - the Preferences tab and the Functions tab.
Use the options in this tab to adjust the display options and the scaling of the timeline. It has a Display group and a Vertical Scaling group. In the Display group, there are six check boxes. These are:
Time Scale: This displays a time scale along the x-axis.
Vertical Scale: This scale is on the y-axis. By default, this option is enabled so that the scale is shown.
Legend: This shows the legend in the right margin of the timeline. This is also enabled by default.
Adjust Graphics to Legend Height: This forces the size of the diagram to be large enough to show all legend items.
Frames: Frames give an outline to the bars. The usage of frames becomes visible only when zooming in very closely such that each bar is separated from the other. Figure 4-15 illustrates the Quantitative Timeline with frames. In this figure, the Application function group is shown with a black outline, while the MPIs are shown with a white outline.
Grid: Use this checkbox to turn the grid on or off. The grid is drawn on top of the data and is aligned with the ticks on the scales. By default, this checkbox is activated.
The vertical scaling option functions the same way as in the Qualitative Timeline (see Section 4.2.2).
The Functions Tab
The Functions Tab selects the functions to be hidden/displayed. It is also possible to change the stacking order with this tab.
Radio buttons in this tab specify whether each individual process is counted (Count individual Processes) or whether merely the uppermost entries of Group All_Processes(Count Top Level Entries of Group All_Processes Only) are counted.
The context menu entry Ungroup in the Quantitative Timeline provides the option of ungrouping the given function group, like in the Function Profile (refer to Section 18.104.22.168). Similarly, Regroup allows undoing a previous ungrouping.
The Hide option in the context menu conceals the chosen activity. To unhide all the hidden items, use the check boxes in the Functions tab of the Settings Dialog box.
The Move Group entry in the context menu changes the position of the different groups. The opted group can be moved to the top, to the bottom, upward by one position or downward by one position. Click on the legend to obtain a context menu with these options.
The other context menu entries are explained in Section 4.8.
Tagging in the Quantitative Timeline is indicated by a mesh pattern being placed over the tagged item. Figure 4-18 shows a Quantitative Timeline for the file poisson_icomm.single.stf with the tagged function MPI_Finalize on the right-hand side of the display.
Filtering in the Quantitative Timeline works the same way as in any other Chart. Figure 4-19 shows the result when only MPI_Finalize passes the filter.