On Fri, 19 Feb 2016, Andrew Morton wrote: > On Fri, 19 Feb 2016 09:40:45 +0300 Konstantin Khlebnikov <koct9i@xxxxxxxxx> wrote: > > > >> What are your thoughts on this? > > > > > > My thoughts are NAK. A misleading stat is not so bad as a > > > misleading stat whose meaning we change in some random kernel. > > > > > > By all means improve Documentation/filesystems/proc.txt on Cached. > > > By all means promote Active(file)+Inactive(file)-Buffers as often a > > > better measure (though Buffers itself is obscure to me - is it intended > > > usually to approximate resident FS metadata?). By all means work on > > > /proc/meminfo-v2 (though that may entail dispiritingly long discussions). > > > > > > We have to assume that Cached has been useful to some people, and that > > > they've learnt to subtract Shmem from it, if slow or no swap concerns them. > > > > > > Added Konstantin to Cc: he's had valuable experience of people learning > > > to adapt to the numbers that we put out. > > > > > > > I think everything will ok. Subtraction of shmem isn't widespread practice, > > more like secret knowledge. This wasn't documented and people who use > > this should be aware that this might stop working at any time. So, ACK. > > It worries me as well - we're deliberately altering the behaviour of > existing userspace code. Not all of those alterations will be welcome! > > We could add a shiny new field into meminfo and train people to migrate > to that. But that would just be a sum of already-available fields. In > an ideal world we could solve all of this with documentation and > cluebatting (and some apologizing!). Ah, I missed this, and just sent a redundant addition to the thread; followed by this doubly redundant addition. Hugh -- 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>