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Recently, I have been working on a patch series [1] with Gregory Price that provides new default interleave weights, along with dynamic re-weighting on hotplug events and a series of UAPIs that allow users to configure how they want the defaults to behave. In introducing these new defaults, discussions have opened up in the community regarding how best to create a UAPI that can provide coherent and transparent interactions for the user. In particular, consider this scenario: when a hotplug event happens and a node comes online with new bandwidth information (and therefore changing the bandwidth distributions across the system), should user-set weights be overwritten to reflect the new distributions? If so, how can we justify overwriting user-set values in a sysfs interface? If not, how will users manually adjust the node weights to the optimal weight? I would like to revisit some of the design choices made for this patch, including how the defaults were derived, and open the conversation to hear what the community believes is a reasonable way to allow users to tune weighted interleave weights. More broadly, I hope to get gather community insight on how they use weighted interleave, and do my best to reflect those workflows in the patch. Of course, I would also love to hear your thoughts about this topic in this thread, or in the RFC thread (attached) as well. Have a great day! Joshua [1] https://lore.kernel.org/all/20241219191845.3506370-1-joshua.hahnjy@gmail.com/