The Preferences dialog is accessed by selecting Instruments > Preferences. It contains six tabs where you can customize Instruments to best suit your needs.
Use the General tab to configure basic Instruments preferences including startup, keyboard shortcuts, and warnings options.
Always use deferred mode
Performs data analysis for all traces after data collection is complete.
Automatically time profile spinning applications
Automatically monitors for a spinning process and starts the Time Profiler instrument on a spinning process. This can be a process other than the one being recorded.
Suppress template chooser
Hides the template chooser when Instruments starts up and when a new trace document is created.
Save current run only
Saves only the current data collection run for each individual instrument.
Compress run data
Compresses each saved run into zip format.
Default document location
Determines the default location for data storage.
Global Keyboard Shortcuts
Sets a keyboard shortcut for starting the time profiling instrument.
Reset “Don’t Ask Me” Warnings
Enables or disables dialog warnings. Instruments has several warning dialogs that you can disable by selecting the “Do not show this message again” checkbox in the dialog. To reenable all of these warning dialogs, click the Reset “Don’t Ask Me” Warnings button.
Use the Display tab to configure track display options in a trace document.
Enforce initial deck height
When selected, saves the current deck height of an instrument. When deselected, uses the template’s default deck height.
Sort process lists by identifier
When selected, sorts all processes by their process ID. When deselected, sorts processes alphabetically.
Always snap track to fit at end of run
Always snap track to fit at end of run: Automatically resizes the track in a trace document to fit the current track width.
Use the DTrace tab to configure how DTrace-based instruments act. DTrace instruments use dynamic tracing to access low-level kernel operations and user processes running on your device.
Sets the size of the DTrace buffer (in megabytes). The default is 25 MB.
Max backtrace depth
Sets the maximum stack depth that is captured when using a DTrace instrument (in megabytes). The default is 25 MB.
Permit zero match probes.
Prevents an error when a specified probe is not found.
Preserve intermediate files
Prevents Instruments from removing intermediate files from the disk.
Flag runtime messages
Adds flags to the timeline for status and error messages encountered during a recording.
Background Profiling Tab
Use the Background Profiling tab to determine how the Time Profiler instrument acts when you access it from the system Dock or from a keyboard shortcut (in these cases, Instruments runs in the background). Set how often information is gathered and the length of automatically captured samples.
Specifies how often a sample is taken. Type a numeric value in the field. Choose microsecond, millisecond, or second from the pop-up menu. Defaults to 1 millisecond
Sets the length of the sample. Type a numeric value in the field. Choose microsecond, millisecond, or second from the pop-up menu. Defaults to 5 seconds.
Use the CPUs tab to configure Instruments for the CPU configuration of your device.
Active Processor Cores
Determines how many cores of your system are used. Use the slider to set the number of active cores equal to the number of cores on the device that you expect your application to run on.
Allows CPU cores to use a second logical core on supported devices. A system with two physical cores would have a total of four cores to use.
dSYMs and Paths Tab
Use the dSYMs and Paths tab to set global search paths for Instruments. Click the plus (+) button to add a new search path.
Adds a search location. Opens the Open Directory dialog. Navigate to the desired directory and click Open.
Removes a search location. Select a path and click the minus (-) button to remove the path.
dSYM Download Script
Provides the option of running a custom script to locate and access the necessary dSYM files. This option is provided for use by large developers with distributed code databases; it is not needed by the majority of developers.
When a run ends
Specifies action to take at the conclusion of the Download Script.