ANDROID PERFORMANCE TUNING MEMORY

SERGII KOZYREVSeniorSE

22.06.2016

Memory

Garbage Collector is such a cool feature

There is always taxes -“performance is not free”? :)

Understanding memory

•GC•Findobjectsthatcan’tbeaccessed•Reclaimtheresources

•Questions:•HeapvsStackmemory?•WhatGCcollects?•Howleakshappens?

Concerns

Memory Leaks

•It’snotonlyaboutOutOfMemoryError

•ItreducesavailablememoryandcausesGCrunmorefrequent- whichisbad

Different VMs – different Logs

•Dalvik (everyGC)•ART(iftheGCpauseexceedsthan5msortheGCdurationexceeds100ms)

Concurrent VSAlloc

DEMO Memory Monitor

Memory Leaks

•Simple- “handlercase”,oreverycircularreferencedobjects

•Complex- holdingahandletotheClassLoader objects,loadinonCreate anddon’tcheckifclassesalreadyloaded(noclassunloadprocedure)

Memory Leaks•StaticActivities,Views,Contextawarestuff

• InnerClasses

•AnonymousClasses

•Handlers

•ThreadsandTimerTask

•SensorManager

DEMO HeapViewver

Move allocations out of inner loops :)

DEMO Allocation Tracker

Thank You!

Links:https://github.com/kozyrevsergey89/PerformanceLab

https://github.com/square/leakcanaryhttps://www.udacity.com/course/android-performance--ud825