One of the most frustrating experiences on an Android phone is when apps are killed in the background. Notifications might stop coming through, whatever you were last doing is gone, and it's an entirely randomized behavior. Some Android phones are better than others, but pretty much all of them will experience it at some point. But a future change in Android, maybe even Android 13, may mean that your apps may not be killed as quickly in the future.

The feature, called "Multi-Generational Least Recently Used" (or MGLRU), has already been rolled out on Chrome OS for some time now, with the company maintaining MGLRU over "a number of different kernels between 4.14 and 5.15". One Googler says that it's become "the default for tens of millions of users", and now it seems that the feature is making its way to Android. A commit on the Android Gerrit shows that Google has merged the change for Android 13's Generic Kernel Image (GKI), and another commit shows that soon, it may even be possible to enable it via adb. That second commit hasn't been merged yet, but it's currently under review.

The feature achieves two major goals that Android users should be very interested in. The first is that Google identified a 40% reduction in kswapd CPU usage, and the second is that Google identified a decrease in 18% of out-of-memory (OOM) app killings on Android. The same Google engineer says that the company tested MGLRU on "one million" Android devices, which seems to be in reference to the Android Runtime on Chrome OS Virtual Machine (ARCVM) which powers Android 11 on Chrome OS.  "We've seen substantial improvements in terms of CPU utilization and memory pressure resulting in fewer OOM kills and reduced UI latency", they wrote.

As for what all of this means, it's fairly simple. kswapd is the process that manages virtual memory, meaning that if there's a 40% reduction in its CPU usage, that's a lot of potential processing headroom being freed up. As for the out-of-memory app killings, that speaks for itself, and will obviously be an immediately tangible benefit to end-users. We've seen plenty of devices that struggle with memory management and delivering notifications on time or app killing in the background.

Currently, it's not clear if Google will test the feature out on some users for Android 13, let alone enable it by default, but it's going to be a benefit to users when it does roll out. We'll be keeping a close eye on this development to see if anything changes in the future.


Source: Android Gerrit (1), (2)

Thanks to XDA Recognized Developer luca020400 for his assistance in this article!