IVI15.1.4 系统稳定性优化篇（LMKD IV）LMKD初始化

Posted 2022-09-02 高桐@BILL

一，LMKD代码架构一览

二，Init

init进程在初始化中会解析init.rc配置信息；当触发名为“early-init”当trigger时，会初始化相关memory.pressure_level节点的用户，用户组等访问权限。

on early-init
    # memory.pressure_level used by lmkd
    chown root system /dev/memcg/memory.pressure_level
    chmod 0040 /dev/memcg/memory.pressure_level
    # app mem cgroups, used by activity manager, lmkd and zygote
    mkdir /dev/memcg/apps/ 0755 system system

随后，在“init”等触发器中执行启动lmkd服务的操作。

on init
    # Start lmkd before any other services run so that it can register them
    write /proc/sys/vm/watermark_boost_factor 0
    chown root system /sys/module/lowmemorykiller/parameters/adj
    chmod 0664 /sys/module/lowmemorykiller/parameters/adj
    chown root system /sys/module/lowmemorykiller/parameters/minfree
    chmod 0664 /sys/module/