On Fri, Aug 05, 2022 at 04:32:34PM -0700, Linus Torvalds wrote: > On Wed, Aug 3, 2022 at 1:35 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > - memcg debug/visibility work from Roman Gushchin > > Well, not just memcg. > > There's that new CONFIG_SHRINKER_DEBUG too. > > Which looks like yet another "people add Kconfig options incorrectly". > > We don't make new features "default y" unless there's some truly > pressing reason for it (ie "99.9% of all people will want this" or "we > used to always compile this in, now it's optional"). Hi Linus! It actually was 'default n' in one of the earlier version of the patchset and has been switched to 'default y' based on the following feedback from Dave Chinner (https://lore.kernel.org/lkml/YmiWK56bOHyrr64u@rh/): No. The argument that "if we turn it off there's no overhead" means one of two things: 1. nobody turns it on and it never gets tested and so bitrots and is useless, or 2. distro's all turn it on because some tool they ship or customer they ship to wants it. Either way, hiding it behind a config option is not an acceptible solution for mering poorly thought out infrastructure. Personally I think that the feature is not that useful for the majority of users (this is why default was n), but it's not adding much of the overhead, so I had no strong reasons to oppose Dave. Cc'ing him just in case. Thanks!
