Writeback (the act of writing modified file data in the background) can sometimes take too much memory. For some kind of block devices, like networking block devices or even USB drives, it can too much. This release adds five new sysfs knobs (strict_limit, min_bytes, max_bytes, min_ratio_fine, max_ratio_fine) under each bdi (block device interface) at /sys/class/bdi/ that allow a finer grained control of the writeback mechanism. For more details read the documentation
Linux 6.2 further refined tunables per BDI.
To highlight: