On Sun 22-08-21 17:46:08, yong w wrote: > > All those reasons should be a part of the changelog. > >.... > > I am not sure these are sufficient justifications but that is something > > to discuss. And hence it should be a part of the changelog. > > > OK, These reasons will be added to the patch notesin later versions. > > > > 3. In the case where the user does not need vmpressure, vmpressure > > > calculation is additional overhead. > > > > You should quantify that and argue why that overhead cannot be further > > reduced without config/boot time knobs. > > > The test results of the previously used PFT tool may not be obvious. > Is there a better way to quantify it? This is a question for you to answer I am afraid. You want to add a configuration option and (as explained) that is not free of cost from the maintenance POV. There must a very good reason to do that. > > > In some special scenes with tight memory, vmpressure will be executed > > > frequently.we use "likely" and "inline" > > > to improve the performance of the kernel, why not reduce some > > > unnecessary calculations? > > > > I am all for improving the code. Is it possible to do it by other means? > > E.g. reduce a potential overhead when there no events registered? > Yes, the method you mentioned may be feasible, but it does not conflict > with this patch. It is not in conflict but runtime overhead reduction without more burden on the configurability is usually a preferred approach. -- Michal Hocko SUSE Labs
