Re: [PATCH 2/2] mm: Consolidate page table accounting

On Thu, Oct 05, 2017 at 10:38:29AM +0530, Anshuman Khandual wrote:

On 10/04/2017 10:06 PM, Kirill A. Shutemov wrote:

quoted

This patch switches page table accounting to single counter from
three -- nr_ptes, nr_pmds and nr_puds.

mm->pgtables_bytes is now used to account page table levels. We use
bytes, because page table size for different levels of page table tree
may be different.

The change has user-visible effect: we don't have VmPMD and VmPUD
reported in /proc/[pid]/status. Not sure if anybody uses them.
(As alternative, we can always report 0 kB for them.)

OOM-killer report is also slightly changed: we now report pgtables_bytes
instead of nr_ptes, nr_pmd, nr_puds.

Could you please mention the motivation of doing this ? Why we are
consolidating the counters which also changes /proc/ interface as
well as OOM report ? What is the benefit ?

Sure, I'll update description.

-- 
 Kirill A. Shutemov