On Mon 27-11-17 09:25:16, Andi Kleen wrote: > Michal Hocko <mhocko@xxxxxxxxxx> writes: > > > > Could you be more explicit about _why_ we need to remove this tunable? > > I am not saying I disagree, the removal simplifies the code but I do not > > really see any justification here. > > It's an arbitrary scaling limit on the how many mappings the process > has. The more memory you have the bigger a problem it is. We've > ran into this problem too on larger systems. Why cannot you increase the limit? > The reason the limit was there originally because it allows a DoS > attack against the kernel by filling all unswappable memory up with VMAs. We can reduce the effect by accounting vmas to memory cgroups. -- Michal Hocko SUSE Labs
