how to trace memory leak in Android ?－觀察筆記

this post is really a question, doesn't contain the answer Orz

this big question may consist of several items

what is memory leak ?

how to monitor Android system memory and performance ？

linux command :

ps -x
top
cat /proc/meminfo

not know exactly :

dumpsys meminfo proc-id
procrank
time command-line
vmstat

and DDMS (Android SDK tool) !!

Could automatic track memory leak on Android ?

DDMS could help !

but need to do some settings ( group discuss Finding Memory leak in native code )

0. Build libc_debug.so

1. replace system/lib/libc.so with /system/lib/libc_debug.so

2. set environment variables

$PATH with ~/open_src/prebuilt/linux-x86/toolchain/arm-eabi-XXX/bin
$ANDROID_PRODUCT_OUT with ~/open_src/out/target/product//

'PATH' is used for getting "arm-eabi-addr2line" and
ANDROID_PRODUCT_OUT for getting the path to /symbol folder.

3. restart the framework.

adb shell stop && adb shell start

4. Add "native=true" to ~/.android/ddms.cfg

5. start the stand-alone version of DDMS. -> "Native Heap"

but just know that there was an malloc @@ !!

how to avoid memory leak in application ?

from Avoid memory leaks on Android suggestion:

Do not keep long-lived references to a context-activity (a reference to an activity should have the same life cycle as the activity itself)
Try using the context-application instead of a context-activity
Avoid non-static inner classes in an activity if you don’t control their life cycle, use a static inner class and make a weak reference to the activity inside

to be continued ...