perf

Compil perf tool and copy it under /system/bin:

 

> make perf
> adb remount ; adb push out/target/product/<platform>/system/bin/perf /system/bin/

 

Top consumer functions:

 

# perf top -a [-p <pid>]
PerfTop: 441 irqs/sec kernel:53.3% exact: 0.0% [1000Hz cycles], (target_pid: 2086)
-------------------------------------------------------------------------------
samples pcnt function DSO
 _______ _____ __________________________________________ _________
 89.00 7.0% dvmAsmInstructionStartCode [vdso]
 53.00 4.1% memcpy [vdso]
 46.00 3.6% copy_user_enhanced_fast_string [kernel]
 33.00 2.6% intel_pmu_enable_all [kernel]
 28.00 2.2% add_preempt_count [kernel]
 28.00 2.2% processMarkStack(GcMarkContext*) [vdso]
 21.00 1.6% hsCheckPointer2AppHeap(Object*, Object*) [vdso]
 18.00 1.4% sub_preempt_count [kernel]
 15.00 1.2% kmem_cache_alloc [kernel]
 14.00 1.1% do_raw_spin_lock [kernel]
 13.00 1.0% dvmJitGetTraceAddrThread [vdso]
 11.00 0.9% debug_smp_processor_id [kernel]
 10.00 0.8% dvmBitVectorIteratorNext(BitVectorIterator [vdso]
 10.00 0.8% kmem_cache_free [kernel]
 10.00 0.8% __might_sleep [kernel]
 10.00 0.8% pthread_mutex_lock [vdso]

 

Task/module/fct repartition Recording (create /data/perf.data):

 

# perf record -a [-p <pid>] sleep 10

 

then, for post-analysis on Host:

 

$ cd out/target/product/<platform>/
$ adb pull /data/perf.data
$ perf report perf.data --symfs=symbols --vmlinux=linux/kernel/vmlinux