Re: [RFC v2] prctl: prctl(PR_SET_IDLE, PR_IDLE_MODE_KILLME), for stateless idle loops

From: peter enderborg
Date: Wed Nov 22 2017 - 05:29:50 EST

On 11/03/2017 07:35 AM, Shawn Landden wrote:
> It is common for services to be stateless around their main event loop.
> If a process sets PR_SET_IDLE to PR_IDLE_MODE_KILLME then it
> signals to the kernel that epoll_wait() and friends may not complete,
> and the kernel may send SIGKILL if resources get tight.
> See my systemd patch:
> Android uses this memory model for all programs, and having it in the
> kernel will enable integration with the page cache (not in this
> series).
> 16 bytes per process is kinda spendy, but I want to keep
> lru behavior, which mem_score_adj does not allow. When a supervisor,
> like Android's user input is keeping track this can be done in user-space.
> It could be pulled out of task_struct if an cross-indexing additional
> red-black tree is added to support pid-based lookup.
What android version is using systemd?
In android there is a OnTrimMemory that is sent from activitymanager that
you can listen on and make a nice exit.