Android memory cgroup topic

[Zhao Junmin]

From android version, we see that Android plan to use memory cgroup to manage process.

In system/core/rootdir/init.rc

    # Create cgroup mount point for memory

    mount tmpfs none /sys/fs/cgroup mode=0750,uid=0,gid=1000

    mkdir /sys/fs/cgroup/memory 0750 root system

    mount cgroup none /sys/fs/cgroup/memory memory

    write /sys/fs/cgroup/memory/memory.move_charge_at_immigrate 1

    chown root system /sys/fs/cgroup/memory/tasks

    chmod 0660 /sys/fs/cgroup/memory/tasks

    mkdir /sys/fs/cgroup/memory/sw 0750 root system

    write /sys/fs/cgroup/memory/sw/memory.swappiness 100

    write /sys/fs/cgroup/memory/sw/memory.move_charge_at_immigrate 1

    chown root system /sys/fs/cgroup/memory/sw/tasks

    chmod 0660 /sys/fs/cgroup/memory/sw/tasks

why Nexus or Samsung don't enable CONFIG_MEMCG=y feature in kernel？

[Hiram Lew]

What version of Android are you referring to? I ask because a new memory management daemon was added in Lollipop which uses memory cgroups -- particularly memory pressure events. Older versions below 5.0 used the kernel-land lowmemorykiller which did not use memory cgroups.

[Zhao Junmin]

HI Lew:

Now we don't use lmkd to manage memory.

We use M version!

Thanks