You can view any system traces that you've [recorded previously](https://developer.android.com/android-performance-analyzer/run) in the
System Profiler in Android Performance Analyzer. This guide demonstrates how to use the trace view to interact with
recorded data. For a detailed description of the data presented in the trace
view, see [Understand trace data](https://developer.android.com/android-performance-analyzer/view/data).
## Navigate the trace view
The trace view provides a variety of ways to interact with the recorded data for
quick, intuitive analysis, as well as support for [custom
queries](https://developer.android.com/android-performance-analyzer/view#custom-queries). Click
**View Keyboard Mouse Shortcuts** in the top-right corner of the trace view for
a list of keyboard and mouse hotkeys.
 **Figure 1**: A screenshot of an example trace view.
### Filter tracks by name
You can type in the **Filter tracks by name** field in the top-left corner of
the trace view to filter expanded tracks down to just the tracks with a name
matching the search string.
### Scroll, pan, and zoom
You can use the following keyboard shortcuts to navigate the trace view:
- A and D (or Left and Right) to pan back and forth in the timeline.
- W and S to zoom in or out.
- Up and Down to scroll vertically.
- Hold Shift while using any of these shortcuts to speed up navigation.
You can also navigate by clicking and dragging, by using the scrollbars on the
right and bottom sides of the trace view, or by scrolling horizontally and
vertically with your trackpad or mouse wheel.
When you open a trace file for the first time, it starts fully zoomed-out so
that the entire timeline is visible. To zoom in or back out again, use
W and S on the keyboard.
### View details
Click an event on any track to open a details panel that presents a more
detailed view of the data collected for that event.
To close a details panel, either click the collapse icon at the top-right of the
panel or press the Esc key.
### Select a time range
You can select a time range by either clicking and dragging on the timeline bar
at the top of the trace view or by clicking and dragging anywhere in the trace
view while holding Ctrl (Cmd on macOS).
To deselect a time range, click anywhere in the trace view outside of the
selected slice.
### Box-select items
You can click and drag a time range across multiple tracks while holding
Shift to box-select items within that time range for all included
tracks.
This also opens a details panel with a tabbed view of tables that contain all
selected items.
### View multiple traces
Android Performance Analyzer inherits UI functionality from the IntelliJ platform, which means
that you can open multiple trace files simultaneously using tabs, windows, or
split views.
One particularly helpful use case for this functionality is opening two trace
files in a vertical split view. This lets you line up timelines for direct
visual comparison.
 **Figure 2**: A screenshot of multiple trace files opened in a vertical split view.
## Customize the trace view
The trace view also provides ways for you to customize it for maximum usefulness
in your workflow.
### Pin and unpin tracks
Pinned tracks appear at the top of the trace view and remain visible as you
scroll down through the available tracks. You can pin a track by clicking the
pin icon that appears when you hover over its name bar. To unpin a track, click
the pin icon again.
### Expand and collapse tracks
Some tracks can be expanded to provide more granular detail or collapsed to take
up less space.
### Add or remove bookmarks
You can bookmark specific points in the timeline by clicking them in the
timeline bar at the top of the trace view. Each bookmark displays a line
extending through all of the tracks in the trace view. You can toggle the
visibility of each bookmark by clicking the corresponding flag on the timeline
bar, or remove a bookmark entirely by right-clicking its flag.
### State persistence
When you close a trace view, the System Profiler saves your pinned tracks,
bookmarks, zoom level, and scroll position. The next time you open the same
trace file, the trace view's state is restored.
To clear your bookmarks, reset your pinned tracks to the default, or both,
click
**Reset Options**.
## Run custom queries
You can click
**SQL** in the top-left corner of the trace view to open the **SQL** tab.
 **Figure 3** : A screenshot of the **SQL** tab.
In the **SQL** tab, you can write custom [PerfettoSQL](https://perfetto.dev/docs/analysis/perfetto-sql-getting-started) queries for
personalized analysis.
- Click  **Run Query** or press Ctrl+Enter (Cmd+Enter on macOS) to run the query.
- Use the navigation buttons at the bottom if your query results extend onto multiple pages.
- Click  **Copy Query** to copy the contents of the query window to the clipboard.
- Click  **History** for a scrollable dropdown list of queries executed previously. Query history is shared across trace files and projects.
- Click  **Trace** in the lop-left corner to return to the trace view.
You can also let your preferred AI agent write a query for you. See [Use AI to
build custom queries](https://developer.android.com/android-performance-analyzer/analyze/ai#ai-queries) for more information.