Re: [patch -mm] mm, vmstat: suppress pcp stats for unpopulated zones in zoneinfo

From: Andrew Morton
Date: Mon Mar 06 2017 - 17:21:43 EST


On Mon, 6 Mar 2017 14:03:32 -0800 (PST) David Rientjes <rientjes@xxxxxxxxxx> wrote:

> After "mm, vmstat: print non-populated zones in zoneinfo", /proc/zoneinfo
> will show unpopulated zones.
>
> The per-cpu pageset statistics are not relevant for unpopulated zones and
> can be potentially lengthy, so supress them when they are not interesting.
>
> Also moves lowmem reserve protection information above pcp stats since it
> is relevant for all zones per vm.lowmem_reserve_ratio.

Well it's not strictly back-compatible, but /proc/zoneinfo is such a
mess that parsers will be few and hopefully smart enough to handle
this.

btw,

pagesets
cpu: 0
count: 118
high: 186
batch: 31
vm stats threshold: 72
cpu: 1
count: 53
high: 186
batch: 31
vm stats threshold: 72

Should the "vm stats threshold" thing be indented further?

Do we need to print it out N times anyway? Can different CPUs have
different values?