Re: [PATCH] x86/mm: Tracking linear mapping split events since boot

Tejun Heo
2021-01-25T20:34:17Z

Hello,

On Mon, Jan 25, 2021 at 12:15:51PM -0800, Dave Hansen wrote:
> > DirectMap4k: 3505112 kB
> > DirectMap2M: 19464192 kB
> > DirectMap1G: 12582912 kB
> > DirectMap2MSplits: 1705
> > DirectMap1GSplits: 20
>
> This seems much more like something we'd want in /proc/vmstat or as a
> tracepoint than meminfo. A tracepoint would be especially nice because
> the trace buffer could actually be examined if an admin finds an
> excessive number of these.

Adding a TP sure can be helpful but I'm not sure how that'd make counters
unnecessary given that the accumulated number of events since boot is what
matters.

Thanks.

--
tejun