Android 系统架构

• Big picture

• GFX 架构

• Video playback

• Drm video

• Camera

• Audio

• APP vs windows

• Binder

• Message handler

• 进程调度

· DL

Used for periodic real timetasks, eg. Videoencoding/decoding

· RT

POSIX “real-time” tasksSCHED_FIFO/SCHED_RR Task priorities: 0 – 99.

· CFS

Scheduling polices

○ SCHED_NORMAL:Normal Unix tasks

○ SCHED_BATCH: Batch (non-interactive) tasks

○ SCHED_IDLE: Low prioritytasks

· Idle

Onekernel thread (idle) per CPU: “swapper/N”.

SCHED_NORMAL:Normal Unix tasks

○SCHED_BATCH: Batch (non-interactive) tasks

○ SCHED_IDLE: Low prioritytasks

• EAS

• 中断系统

• Memory

• IO stack