Poslab SOMB-iMX6, User Manual

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User Manual
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If you are not using Eclipse and ADT, read Configuring your IDE to attach to the debugging
port, for more information on attaching your debugger.
Tip: You can set a number of DDMS preferences in File > Preferences. Preferences are
saved to $HOME/.android/ddms.cfg.
Known debugging issues with Dalvik
Debugging an application in the Dalvik VM should work the same as it does in other VMs.
However, when single-stepping out of synchronized code, the "current line" cursor may
jump to the last line in the method for one step.
Using DDMS
The following sections describe how to use DDMS and the various tabs and panes that are
part of the DDMS GUI. The Eclipse version and the command line version have minor UI
differences, but the same functionality. For information on running DDMS, see the previous
section in this document, Running DDMS.
Viewing heap usage for a process
DDMS allows you to view how much heap memory a process is using. This information
is useful in tracking heap usage at a certain point of time during the execution of your
application.
To view heap usage for a process:
In the Devices tab, select the process that you want to see the heap information for.
Click the Update Heap button to enable heap information for the process.
In the Heap tab, click Cause GC to invoke garbage collection, which enables the collection
of heap data. When the operation completes, you will see a group of object types and the
memory that has been allocated for each type. You can click Cause GC again to refresh
the data.
Click on an object type in the list to see a bar graph that shows the number of objects
allocated for a particular memory size in bytes.
Tracking memory allocation of objects
DDMS provides a feature to track objects that are being allocated to memory and to see
which classes and threads are allocating the objects. This allows you to track, in real time,
where objects are being allocated when you perform certain actions in your application.
This information is valuable for assessing memory usage that can affect application
performance.
To track memory allocation of objects:
In the Devices tab, select the process that you want to enable allocation tracking for.
In the Allocation Tracker tab, click the Start Tracking button to begin allocation tracking. At
this point, anything you do in your application will be tracked.