F2FS File-System Driver Preparing A Low-Memory Mode

Google engineers are working on the notion of "memory modes" for the Flash-Friendly File-System (F2FS) with the intent on introducing a "low memory" mode for storage devices that would alter its behavior. Presumably Google is working on this new F2FS feature for low-end Android devices.

With the F2FS patch in development the memory mode is plumbing the "normal" mode of operation as well as the new low memory mode. Google's Daeho Jeong simply sums up the intent of the low memory mode as, "Because of the nature of low memory devices, in this mode, f2fs will try to save memory sometimes by sacrificing performance."

This low memory mode can be activated via the f2fs.memory=low kernel module parameter to change the behavior of the F2FS file-system driver to help conserve storage space at the cost of performance.

The exact behavioral changes made by the F2FS memory mode appears to be a work in progress with this patch simply introducing the infrastructure for the memory mode and the new memory= parameter. In any event look for F2FS' low memory mode being tuned soon for more efficient dealing with lower amounts of memory. The patch is currently in the F2FS "dev" branch so at least that basic infrastructure is likely to be mainlined for the Linux 5.20 cycle later this summer.