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| <title>Debugging Native Memory Use</title> |
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| |
| <h2 id="asan">Address Sanitizer</h2> |
| |
| <p>Android platform developers use <a href="/devices/tech/debug/asan.html">AddressSanitizer</a> |
| (ASan) to find memory bugs in C/C++.</p> |
| |
| </p>Since Android 8.0 (Oreo) it's also possible to use ASan to debug apps on non-rooted production |
| devices. You can find instructions on the |
| <a href="https://github.com/google/sanitizers/wiki/AddressSanitizerOnAndroidO">ASan wiki</a>.</p> |
| |
| <h2 id="malloc_debug">Malloc debug</h2> |
| |
| <p>See <a |
| href="https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README.md">Malloc |
| Debug</a> and <a |
| href="https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README_api.md">Native |
| Memory Tracking using libc Callbacks</a> for a thorough description of the |
| debugging options available for native memory issues.</p> |
| |
| <h2 id="malloc-stats">Malloc statistics</h2> |
| |
| <p> |
| Android supports the <a href="http://man7.org/linux/man-pages/man3/mallinfo.3.html" |
| ><code>mallinfo(3)</code></a>and <a href="http://man7.org/linux/man-pages/man3/malloc_info.3.html" |
| ><code>malloc_info(3)</code></a> extensions to <code><malloc.h></code></a>. |
| The <code>malloc_info</code> function is available in Android 6.0 and later and |
| its XML schema is documented in Bionic's |
| <a href="https://android.googlesource.com/platform/bionic/+/master/libc/include/malloc.h" |
| ><code><malloc.h></code></a>. |
| </p> |
| |
| <h2 id="ddms">Dalvik Debug Monitor Server</h2> |
| |
| <p>You can also use the <a |
| href="https://developer.android.com/studio/profile/ddms.html">Dalvik Debug |
| Monitor Server</a> (DDMS) to obtain a graphical view of Malloc Debug |
| output.</p> |
| |
| <p>To use DDMS, first turn on its native memory UI:</p> |
| <ol> |
| <li>Open <code>~/.android/ddms.cfg</code></li> |
| <li>Add the line: <code>native=true</code></li> |
| </ol> |
| |
| <p>Upon relaunching DDMS and selecting a process, you can switch to the new |
| native allocation tab and populate it with a list of allocations. This is |
| especially useful for debugging memory leaks.</p> |
| |
| </body> |
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