On Tue 19-01-21 11:58:42, Johannes Weiner wrote: > On Tue, Jan 19, 2021 at 01:27:44PM +0800, Muchun Song wrote: > > The current memcg will be freed soon, so updating it's vmstat and > > vmevent values is pointless. Just skip updating it. > > > > Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> > > Oof, that's pretty subtle! Somebody trying to refactor that code for > other purposes may not immediately notice that optimization and add > potentially tedious bugs. Absolutely agreed! > How much does this save? Cgroup creation and deletion isn't really > considered a hot path. It takes global locks and such... This is not the first time when an (micro)optimization is posted without any data showing benefit or otherwise appealing justification. Sigh. -- Michal Hocko SUSE Labs
