Re: [RFC/PATCHSET 0/6] perf kmem: Implement page allocation analysis (v1)

Namhyung Kim
2015-03-13T08:20:28Z

Hi Ingo,

On Thu, Mar 12, 2015 at 04:54:22PM +0100, Ingo Molnar wrote:
>
> * Namhyung Kim <namhyung@kernel.org> wrote:
>
> > > I.e. something like this (mockup) output:
> > >
> > > SUMMARY (page allocator)
> > > ========================
> > >
> > > Pages allocated+freed: 12,593 [ 51,630,080 bytes ]
> > >
> > > Pages allocated-only: 2,342 [ 1,235,010 bytes ]
> > > Pages freed-only: 67 [ 135,311 bytes ]
> > >
> > > Page allocation failures : 0
> >
> > Looks a lot better!
> >
> > One thing I need to tell you is that the numbers are not pages but
> > requests.
>
> Yes, but in the MM code we tend to call larger order allocations
> 'pages' as well: higher order pages, such as a 2MB hugepage, or a 8K
> order-1 page. So at least in MM-speak it should be OK to call them
> 'pages'.
>
> But your call!

How about this?

SUMMARY (page allocator)
========================
Total allocation requests : 9,015 [ 37,200 Kbytes ] (A)
Total free requests : 8,093 [ 33,176 Kbytes ] (B)

Total alloc+freed requests : 7,985 [ 32,732 Kbytes ] (C)
Total alloc-only requests : 1,030 [ 4,468 Kbytes ] (D)
Total free-only requests : 108 [ 444 Kbytes ] (E)

Total allocation failure : 0 [ 0 Kbytes ]

(A) = (C) + (D)
(B) = (C) + (E)

Thanks,
Namhyung