On Tue 26-09-17 19:45:45, Yafang Shao wrote: > 2017-09-26 19:26 GMT+08:00 Michal Hocko <mhocko@xxxxxxxxxx>: > > On Tue 26-09-17 19:06:37, Yafang Shao wrote: [...] > >> Anyway, there's no document on that direct limits should not less than > >> background limits. > > > > Then improve the documentation. > > I have improved the kernel documentation as well, in order to make it > more clear for the newbies. Why do we need to update the code then? > >> > To be honest I am not entirely sure this is worth the code and the > >> > future maintenance burden. > >> I'm not sure if this code is a burden for the future maintenance, but > >> I think that if we don't introduce this code it is a burden to the > >> admins. > > > > anytime we might need to tweak background vs direct limit we would have > > to change these checks as well and that sounds like a maint. burden to > > me. > > Would pls. show me some example ? What kind of examples would you like to see. I meant that if the current logic of bacground vs. direct limit changes the code to check it which is at a different place IIRC would have to be kept in sync. That being said, this is my personal opinion, I will not object if there is a general consensus on merging this. I just believe that this is not simply worth adding a single line of code. You can then a lot of harm by setting different values which would pass the added check. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>