On Wed, Oct 23, 2019 at 11:01:04PM +0800, Waiman Long wrote: > On 10/23/19 10:48 AM, Qian Cai wrote: > >>> this still isn't a bulletproof fix. Maybe just terminate the list > >>> walk if freecount reaches 1024. Would anyone really care? > >>> > >>> Sigh. I wonder if anyone really uses this thing for anything > >>> important. Can we just remove it all? > >>> > >> Removing it will be a breakage of kernel API. > > Who cares about breaking this part of the API that essentially nobody will use > > this file? > > > There are certainly tools that use /proc/pagetypeinfo and this is how > the problem is found. I am not against removing it, but we have to be > careful and deprecate it in way that minimize user impact. We have been using the /proc/pagetypeinfo for debugging, mainly for client platforms like phones/tablets. We met problems like very slow system response or OOM things, and many of them could be related with memory pressure or fragmentation issues, where monitoring /proc/pagetypeinfo will be very useful for debugging. So I think Michal's idea to change it to 0400 is a good idea. Thanks, Feng > Cheers, > Longman > >
